Compressor

ABSTRACT

A compressor includes a rotary shaft, a rotating body, which rotates together with the rotary shaft, and a fixed body, which does not rotate together with the rotary shaft. The rotating body has a rotating body surface, and the fixed body has a fixed body surface facing the rotating body surface in the axial direction. The compressor includes a vane, which is inserted in a vane groove provided in the rotating body, and a compression chamber, which is defined by the rotating body surface and the fixed body surface. The vane includes a vane body, which is inserted in the vane groove, and a tip seal, which is movable in the axial direction relative to the vane body.

BACKGROUND

1. Field

The present disclosure relates to a compressor.

2. Description of Related Art

Japanese Laid-Open Patent Publication No. 2015-14250 describes an axialvane compressor that includes a rotary shaft, a columnar rotor, whichhas slit grooves, vanes fitted in the slit grooves to be allowed toswing, and side plates having cam surfaces. Each cam surface serves as afixed body surface provided in the side plate, which serves as a fixedbody. Rotation of the rotary shaft and the rotor of this axial vanecompressor causes the vanes to rotate while moving in the axialdirection of the rotary shaft. This results in suction and compressionof the fluid in the compression chambers defined by the axial end facesof the rotor and the cam surfaces.

If the vanes are spaced apart from the fixed body surfaces, the fluidmay leak through the gap between the vanes and the fixed body surfaces.This increases the loss of the compressor and thus lowers theefficiency.

SUMMARY

It is an objective of the present disclosure to provide a compressorthat reduces the likelihood of a gap created between the vanes and thefixed body surfaces.

This Summary is provided to introduce a selection of concepts in asimplified form that are further described below in the DetailedDescription. This Summary is not intended to identify key features oressential features of the claimed subject matter, nor is it intended tobe used as an aid in determining the scope of the claimed subjectmatter.

In one general aspect, a compressor is provided that includes a rotaryshaft, a rotating body, a fixed body, a vane, and a compression chamber.The rotating body is configured to rotate together with the rotary shaftand includes a rotating body surface, which intersects with an axialdirection of the rotary shaft, and a vane groove. The fixed body isconfigured not to rotate together with the rotary shaft and includes afixed body surface, which faces the rotating body surface in the axialdirection. The vane is inserted in the vane groove and configured torotate together with the rotating body while moving in the axialdirection. The compression chamber is defined by the rotating bodysurface and the fixed body surface and in which suction and compressionof fluid is performed when the vane rotates while moving in the axialdirection. The vane includes a vane body inserted in the vane groove anda sealing member attached to an end face in the axial direction of thevane body so as to be movable in the axial direction relative to thevane body. A back pressure space is located between the sealing memberand the vane body. The sealing member is configured to be pressed by theback pressure space toward the fixed body surface so as to be in contactwith the fixed body surface.

Other features and aspects will be apparent from the following detaileddescription, the drawings, and the claims.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic diagram of a compressor according to a firstembodiment.

FIG. 2 is an exploded perspective view of the main components of thecompressor of FIG. 1.

FIG. 3 is an exploded perspective view of the main components as viewedin the opposite direction from FIG. 2.

FIG. 4 is a cross-sectional view of the main components of thecompressor of FIG. 1.

FIG. 5 is a side view of the main components of the compressor of FIG.1.

FIG. 6 is a cross-sectional view taken along line 6-6 in FIG. 4.

FIG. 7 is a cross-sectional view taken along line 7-7 in FIG. 4.

FIG. 8 is an exploded perspective view of a front cylinder, a frontvalve, and a front retainer of the compressor of FIG. 1.

FIG. 9 is an enlarged cross-sectional view of the configuration around avane in the compressor of FIG. 1.

FIG. 10 is a perspective view of a rotating body and vanes of thecompressor of FIG. 1.

FIG. 11 is an exploded perspective view of a vane of FIG. 10.

FIG. 12 is a cross-sectional view schematically showing how a vane is incontact with two fixed body surfaces in the compressor of FIG. 1.

FIG. 13 is a cross-sectional view taken along line 13-13 in FIG. 9.

FIG. 14 is a developed view schematically showing the rotating body, thetwo fixed bodies, and the vanes of the compressor of FIG. 1.

FIG. 15 is a developed view schematically showing the rotating body, thetwo fixed bodies, and the vanes at a phase different from that in FIG.14.

FIG. 16 is a cross-sectional view schematically showing how a vane is incontact with two fixed body surfaces according to a second embodiment.

FIG. 17 is a cross-sectional view schematically showing how a vane is incontact with two fixed body surfaces according to a third embodiment.

FIG. 18 is a cross-sectional view schematically showing how a vane is incontact with two fixed body surfaces according to a fourth embodiment.

FIG. 19 is a cross-sectional view schematically showing tip seals of amodification.

FIG. 20 is a cross-sectional view schematically showing a compressor ofanother modification.

Throughout the drawings and the detailed description, the same referencenumerals refer to the same elements. The drawings may not be to scale,and the relative size, proportions, and depiction of elements in thedrawings may be exaggerated for clarity, illustration, and convenience.

DETAILED DESCRIPTION

This description provides a comprehensive understanding of the methods,apparatuses, and/or systems described. Modifications and equivalents ofthe methods, apparatuses, and/or systems described are apparent to oneof ordinary skill in the art. Sequences of operations are exemplary, andmay be changed as apparent to one of ordinary skill in the art, with theexception of operations necessarily occurring in a certain order.Descriptions of functions and constructions that are well known to oneof ordinary skill in the art may be omitted.

Exemplary embodiments may have different forms, and are not limited tothe examples described. However, the examples described are thorough andcomplete, and convey the full scope of the disclosure to one of ordinaryskill in the art.

First Embodiment

Referring to the drawings, a first embodiment of a compressor will nowbe described. The compressor of the present embodiment may be used for avehicle. Specifically, the compressor may be mounted on a vehicle. Thecompressor may be used for a vehicle air conditioner, and the fluidcompressed by the compressor may be a refrigerant containing oil. Forconvenience of illustration, FIG. 1 shows a rotary shaft 12, a rotatingbody 60, and two fixed bodies 90 and 110 in side views. In addition,FIGS. 6 and 7 schematically show vanes 131 in side views.

As shown in FIG. 1, the compressor 10 includes a housing 11, a rotaryshaft 12, an electric motor 13, an inverter 14, a front cylinder 30,which serves as a cylinder portion, a rear plate 40, a rotating body 60,a front fixed body 90, and a rear fixed body 110.

The housing 11 may be cylindrical as a whole and includes a suction port11 a, through which fluid is drawn from outside, and a discharge port 11b, through which the compressed fluid is discharged. The housing 11accommodates the rotary shaft 12, the electric motor 13, the inverter14, the front cylinder 30, the rear plate 40, the rotating body 60, andthe two fixed bodies 90 and 110.

The housing 11 includes a front housing member 21, a rear housing member22, and an inverter cover 25.

The front housing member 21 has a circumferential wall, an end walllocated at one end in the axial direction of the circumferential wall,and an open end opening toward the rear housing member 22. The suctionport 11 a may be provided in the circumferential wall of the fronthousing member 21 at a position closer to the end wall than to the openend. However, the suction port 11 a may be provided at any position.

The cylindrical rear housing member 22 includes a rear housing end wall23 and a rear housing circumferential wall 24 extending from the rearhousing end wall 23 toward the front housing member 21. The fronthousing member 21 and the rear housing member 22 are combined as oneunit with their open ends facing each other. The discharge port 11 b isprovided in the rear housing circumferential wall 24. However, thedischarge port 11 b may be provided at any position.

The inverter cover 25 and the rear housing member 22 are located on theopposite sides of the front housing member 21. The inverter cover 25 isbutted against and fixed to the end wall of the front housing member 21.The inverter cover 25 accommodates the inverter 14, which actuates theelectric motor 13.

As shown in FIG. 1, the front cylinder 30 cooperates with the rear plate40 and accommodates the two fixed bodies 90 and 110 and the rotatingbody 60. The front cylinder 30 is cylindrical and smaller in diameterthan the circumferential wall 24 of the rear housing member 22. Thefront cylinder 30 opens toward the rear housing end wall 23.

The front cylinder 30 includes a front cylinder end wall 31 and a frontcylinder circumferential wall 32 extending from the front cylinder endwall 31 toward the rear housing end wall 23.

As shown in FIGS. 1 and 2, the front cylinder end wall 31 has stepsarranged in the axial direction Z of the rotary shaft 12, and includes afirst end wall 31 a, which is closer to the center, and a second endwall 31 b, which is located on the outer side of the first end wall 31 ain the radial direction R of the rotary shaft 12. The second end wall 31b is displaced from the first end wall 31 a toward the rear housing endwall 23. The first end wall 31 a has a front insertion hole 31 c, whichreceives the rotary shaft 12.

As shown in FIG. 1, the front cylinder circumferential wall 32 ispositioned inside the rear housing member 22. The front cylindercircumferential wall 32 has a front cylinder inner circumferentialsurface 33 and a front cylinder outer circumferential surface 34, whichis on the opposite side from the front cylinder inner circumferentialsurface 33.

The front cylinder inner and outer circumferential surfaces 33 and 34may be cylindrical surfaces having an axis extending in the axialdirection Z of the rotary shaft 12. The front cylinder outercircumferential surface 34 is in contact with the inner circumferentialsurface of the rear housing circumferential wall 24 in the radialdirection R.

The front cylinder outer circumferential surface 34 includes a dischargerecess 35 defining a discharge chamber A1. The discharge recess 35 isprovided between the two axial ends of the front cylinder outercircumferential surface 34 and is recessed radially inward. Thedischarge recess 35 and the rear housing circumferential wall 24 definethe discharge chamber A1 containing the compressed fluid. The dischargechamber A1 is cylindrical and has an axis extending in the axialdirection Z of the rotary shaft 12. The discharge chamber A1 iscontinuous with the discharge port 11 b. The compressed fluid in thedischarge chamber A1 is discharged through the discharge port 11 b.

The front cylinder 30 has a bulging section 36 projecting outward in theradial direction. The bulging section 36 connects the front cylinder endwall 31 to the front cylinder circumferential wall 32. The bulgingsection 36 projects radially outward from the front cylinder outercircumferential surface 34. The front housing member 21 and the rearhousing member 22 are coupled to each other with the bulging section 36sandwiched between them. The housing members 21 and 22 limitdisplacement of the front cylinder 30 in the axial direction Z.

As shown in FIG. 1, the front housing member 21 and the front cylinderend wall 31 define a motor chamber A2 in the housing 11. The motorchamber A2 accommodates the electric motor 13. When the electric poweris supplied from the inverter 14, the electric motor 13 rotates therotary shaft 12 in the direction indicated by arrow M, specifically, inthe clockwise direction as viewed in the direction from the electricmotor 13 to the two fixed bodies 90 and 110.

Since the suction port 11 a is provided in the front housing member 21,which defines the motor chamber A2, the fluid entering through thesuction port 11 a is drawn into the motor chamber A2 in the housing 11.That is, the motor chamber A2 contains the fluid drawn through thesuction port 11 a. The motor chamber A2 is a suction chamber into whichthe fluid is drawn.

In the compressor 10 of this embodiment, the inverter 14, the electricmotor 13, the front fixed body 90, the rotating body 60, and the rearfixed body 110 are arranged in this order in the axial direction Z.However, the positions of these components may be changed, and theinverter 14 may be located radially outward from the electric motor 13,for example.

The rear plate 40 is planar (has the shape of a circular plate in thepresent embodiment) and accommodated in the rear housing member 22 suchthat its thickness direction coincides with the axial direction Z. Theouter diameter of the rear plate 40 may be the same as the diameter ofthe front cylinder outer circumferential surface 34 (or the innercircumferential surface of the rear housing circumferential wall 24).The rear plate 40 is fitted into and supported by the rear housingmember 22.

The rear plate 40 is separate from the front cylinder end wall 31. Thefront cylinder 30 and the rear plate 40 are assembled such that thedistal end (open end) of the front cylinder circumferential wall 32 isbutted against the rear plate 40. The rear plate 40 closes the openingof the front cylinder 30.

Specifically, the rear plate 40 has a plate recess 42 in the positionfacing the distal end of the front cylinder circumferential wall 32 inthe axial direction Z. The plate recess 42 extends over the entirecircumference. The front cylinder 30 is coupled to the rear plate 40with the distal end of the front cylinder circumferential wall 32 fittedinto the plate recess 42.

The housing 11 supports the rear plate 40. Specifically, the rear plate40 is held between the front cylinder 30, which is supported by thehousing 11, and the rear housing end wall 23, which is a part of thehousing 11. This may be changed as long as the housing 11 supports therear plate 40.

The rear plate 40 has a first plate surface 43 and a second platesurface 44 extending orthogonal to the axial direction Z. The firstplate surface 43 faces away from the rear housing end wall 23. Thesecond plate surface 44 faces the rear housing end wall 23 in the axialdirection Z. Since the present embodiment has the plate recess 42, thefirst plate surface 43 is smaller than the second plate surface 44.

As used herein, the term “face” refers to a state where two members faceeach other with a gap created between them, and also a state where thetwo members are in contact with each other. For example, the secondplate surface 44 and the rear housing end wall 23 may be spaced apartfrom each other or in contact with each other. The term “face” alsorefers to a state where two surfaces face each other with parts of thesurfaces are in contact with each other and other parts are spaced apartfrom each other.

As shown in FIG. 1, the compressor 10 includes shaft bearings 51 and 53,which support the rotary shaft 12 in a rotatable manner.

The front shaft bearing 51 is attached to a boss 52 provided on the endwall of the front housing member 21. The boss 52 is ring-shaped andprotrudes from the end wall of the front housing member 21. The frontshaft bearing 51 is located radially inward from the boss 52 andsupports a front shaft end 12 a in a rotatable manner. The front shaftend 12 a is one of the two axial shaft ends 12 a and 12 b of the rotaryshaft 12.

The central section of the rear plate 40 has a rear insertion hole 41,which receives the rotary shaft 12. The diameter of the rear insertionhole 41 is greater than or equal to the diameter of the rear shaft end12 b. The rear shaft end 12 b is inserted in the rear insertion hole 41.

The inner wall surface defining the rear insertion hole 41 includes arear shaft bearing 53, which supports the rear shaft end 12 b in arotatable manner. The rear shaft bearing 53 may be a coating bearingformed by a coating layer on the inner wall surface defining the rearinsertion hole 41.

The coating layer may be changed and include a thermosetting resin or alubricant. Further, the rear shaft bearing 53 does not have to be thecoating bearing formed by the coating layer, and may be other slidingbearings or rolling bearings. FIG. 1 shows the rear shaft bearing 53thicker than the actual size.

In the present embodiment, the two shaft bearings 51 and 53 support theshaft ends 12 a and 12 b in a rotatable manner. The front shaft bearing51 is attached to the boss 52 of the front housing member 21, and therear housing member 22 supports the rear plate 40 including the rearshaft bearing 53. As such, the rotary shaft 12 may be considered asbeing supported by the housing 11 with the shaft bearings 51 and 53 soas to be rotatable relative to the housing 11. In the presentembodiment, the rotary shaft 12 is columnar.

As shown in FIG. 1, the rear housing end wall 23 includes a housingrecess 54 in the position facing the rotary shaft 12 in the axialdirection Z. The housing recess 54 is circular and slightly larger thanthe rear shaft end 12 b, for example. A part of the rear shaft end 12 bis located in the housing recess 54.

The compressor 10 includes a ring plate 55 placed in the housing recess54, and the ring plate 55 limits displacement of the rotary shaft 12 inthe axial direction Z. The ring plate 55 may be a flat ring fitted intothe housing recess 54. The outer diameter of the ring plate 55 may beequal to the inner diameter of the housing recess 54. The ring plate 55is arranged between the rear shaft end 12 b and the bottom surface ofthe housing recess 54. The section of the rotary shaft 12 other than thefront shaft end 12 a is located between the front shaft bearing 51 andthe ring plate 55 in the axial direction Z. This limits movement of therotary shaft 12 in the axial direction Z. However, to accommodatedimensional errors, a small clearance may be provided between the ringplate 55 and the rear shaft end 12 b.

As shown in FIG. 1, in the housing 11, the front cylinder 30 and therear plate 40 define an accommodation chamber A3, which accommodates therotating body 60 and the two fixed bodies 90 and 110.

The motor chamber A2 and the accommodation chamber A3 are arranged inthe axial direction Z in the housing 11. The front cylinder end wall 31separates the motor chamber A2 from the accommodation chamber A3 so thatthe fluid in the motor chamber A2 does not flow into the accommodationchamber A3. The front cylinder end wall 31 serves as a partition wallthat separates the motor chamber A2 from the accommodation chamber A3and limits migration of the fluid from the motor chamber A2 to theaccommodation chamber A3. The rotary shaft 12, which extends through thefront cylinder end wall 31 serving as the partition wall, is located inboth of the motor chamber A2 and the accommodation chamber A3. The rearplate 40 serves as a defining portion used to define the accommodationchamber A3.

Referring to FIGS. 2 to 5, the details of the rotating body 60 will nowbe described. For the convenience of illustration, FIG. 5 shows therotating body 60 in a different rotational position, that is, at adifferent phase, from that in FIG. 4.

As the rotary shaft 12 rotates, the rotating body 60 rotates in arotation direction M. The rotational axis of the rotating body 60 placedin the housing 11 coincides with the center axis of the rotary shaft 12.That is, the rotating body 60 is coaxial with the rotary shaft 12.Accordingly, the compressor 10 performs concentric motion instead ofeccentric motion.

The rotating body 60 includes a rotating body tube 61, which receivesthe rotary shaft 12, and a rotating body ring 70, which extends radiallyoutward from the rotating body tube 61.

The rotating body tube 61 is coupled to the rotary shaft 12 so as torotate together with the rotary shaft 12. Rotation of the rotary shaft12 thus rotates the rotating body 60. The rotating body tube 61 may becoupled to the rotary shaft 12 in any manner. For example, the rotatingbody tube 61 may be fixed to the rotary shaft 12 by press-fitting, or afixing pin may extend through the rotary shaft 12 and the rotating bodytube 61 to fix the rotating body tube 61 to the rotary shaft 12. Therotating body tube 61 may be coupled to the rotary shaft 12 by acoupling member, such as a key. Further, the rotating body tube 61 maybe connected to the rotary shaft 12 by the engagement between a recessprovided in one of them and a projection provided in the other.

The rotating body tube 61 is a cylindrical member having an axisextending in the axial direction Z, for example. The rotating body tube61 may have an inner diameter that is greater than or equal to thediameter of the rotary shaft 12. The inner circumferential surface ofthe rotating body tube 61 faces the outer circumferential surface of therotary shaft 12 in the radial direction R.

The rotating body tube 61 has a tube outer circumferential surface 62having an axis extending in the axial direction Z. The tube outercircumferential surface 62 curves radially outward and is a tubularsurface in this embodiment.

As shown in FIGS. 2 to 4, the rotating body ring 70 may be located at anarbitrary position (in the central section in the present embodiment)between opposite rotating body ends 61 a and 61 b, which are axial endsof the rotating body tube 61.

The rotating body ring 70 is an annular plate having a plate thicknessin the axial direction Z. The rotating body ring 70 includes two axialend faces, a front rotating body surface 71 and a rear rotating bodysurface 72. These rotating body surfaces 71 and 72 are ring-shaped. Thetwo rotating body surfaces 71 and 72 intersect with the axial directionZ. In the present embodiment, the rotating body surfaces 71 and 72 areflat surfaces extending orthogonal to the axial direction Z. Thus, theinner and outer edges of the rotating body surfaces 71 and 72 extendlinearly as viewed in the radial direction R, and the entirecircumference of each edge is located in the same position in the axialdirection Z.

The rotating body ring 70 has a ring outer circumferential surface 73,which intersects with the radial direction R. The ring outercircumferential surface 73 faces the front cylinder innercircumferential surface 33 in the radial direction R. The ring outercircumferential surface 73 and the front cylinder inner circumferentialsurface 33 may be in contact with each other, or may be spaced apartfrom each other by a small gap.

As shown in FIG. 4, the compressor 10 includes thrust bearings 81 and82, which support the rotating body 60 in the axial direction Z. Thethrust bearings 81 and 82 are located on the opposite axial ends of therotating body tube 61 and sandwich the rotating body tube 61 in theaxial direction Z.

Specifically, the front thrust bearing 81 is located in a space createdby the steps in the front cylinder end wall 31. The front thrust bearing81, which is supported by the front cylinder end wall 31, supports therotating body tube 61 (specifically, the front rotating body end 61 a)in the axial direction Z.

The rear thrust bearing 82 is located in a thrust accommodation recess83 provided in the rear plate 40. The thrust accommodation recess 83 isprovided in a section of the inner wall surface defining the rearinsertion hole 41 that is adjacent to the first plate surface 43. Therear thrust bearing 82, which is supported by the rear plate 40,supports the rotating body tube 61 (specifically, the rear rotating bodyend 61 b) in the axial direction Z.

The two thrust bearings 81 and 82 are shaped as circular plates andreceive the rotary shaft 12. In the present embodiment, the innercircumference surfaces of the thrust bearings 81 and 82 are in contactwith the outer circumference surface of the rotary shaft 12. The thrustbearings 81 and 82 are in contact with the rotary shaft 12 in the radialdirection R and thus support the rotary shaft 12. However, the thrustbearings 81 and 82 may be spaced apart from the rotary shaft 12 in theradial direction R.

The fixed bodies 90 and 110 are arranged on the opposite sides of therotating body ring 70 in the axial direction. That is, the fixed bodies90 and 110 are spaced apart from each other in the axial direction Zwith the rotating body ring 70 located between them. In other words, therotating body ring 70 is positioned between the two fixed bodies 90 and110.

The fixed bodies 90 and 110 are fixed to the front cylinder 30 (i.e.,the housing 11) so as not to rotate together with the rotary shaft 12.For example, the fixed bodies 90 and 110 are fastened to the frontcylinder circumferential wall 32 using fasteners (not shown) extendingthrough the front cylinder circumferential wall 32. The fixed bodies 90and 110 are thus fixed to the front cylinder 30.

However, the two fixed bodies 90 and 110 may be fixed to the frontcylinder 30 by any method, such as press-fitting and mating. One or morefastening sections may be provided to fasten the front fixed body 90 tothe front cylinder end wall 31, and one or more fastening sections maybe provided to fasten the rear fixed body 110 to the rear plate 40.

The structure of the two fixed bodies 90 and 110 will now be describedin detail. In this embodiment, the fixed bodies 90 and 110 have the sameshape.

As shown in FIGS. 1 to 4, the front fixed body 90, which is one of thefixed bodies 90 and 110 that is located closer to the front cylinder endwall 31, in other words, closer to the motor chamber A2, is ring-shaped(annular in this embodiment) and has a front fixed body insertion hole91, which receives the rotary shaft 12. In the present embodiment, thefront fixed body insertion hole 91 is a through hole extending throughthe front fixed body 90 in the axial direction Z. The front fixed body90 is located in the front cylinder 30 with the rotary shaft 12 insertedin the front fixed body insertion hole 91.

The front fixed body 90 has a front fixed body outer circumferentialsurface 92 facing the front cylinder inner circumferential surface 33 inthe radial direction R. In the present embodiment, the front fixed bodyouter circumferential surface 92 is in contact with the front cylinderinner circumferential surface 33. However, the present disclosure is notlimited to this, and the front cylinder inner circumferential surface 33may be spaced apart from the front fixed body outer circumferentialsurface 92.

The front fixed body 90 includes a front back surface 93 facing thefront cylinder end wall 31 in the axial direction Z. The front backsurface 93 and the inner bottom surface 31 d of the front cylinder endwall 31 may be spaced apart from each other or in contact with eachother.

As shown in FIGS. 1 to 4, in the same manner as the front fixed body 90,the rear fixed body 110, which is one of the fixed bodies 90 and 110that is located closer to the rear plate 40 serving as the definingportion, in other words, located farther from the motor chamber A2, isring-shaped (annular in this embodiment) and has a rear fixed bodyinsertion hole 111, which receives the rotary shaft 12. In the presentembodiment, the rear fixed body insertion hole 111 is a through holeextending through the rear fixed body 110 in the axial direction Z. Therear fixed body 110 is located in the front cylinder 30 with the rotaryshaft 12 inserted in the rear fixed body insertion hole 111. That is, inthis embodiment, the rotary shaft 12 extends through the two fixedbodies 90 and 110 in the axial direction Z.

The rear fixed body 110 has a rear fixed body outer circumferentialsurface 112 facing the front cylinder inner circumferential surface 33in the radial direction R. In the present embodiment, the rear fixedbody outer circumferential surface 112 is in contact with the frontcylinder inner circumferential surface 33. However, the presentdisclosure is not limited to this, and the rear fixed body outercircumferential surface 112 may be spaced apart from the front cylinderinner circumferential surface 33.

The rear fixed body 110 includes a rear back surface 113 that faces thefirst plate surface 43 of the rear plate 40 in the axial direction Z.The rear back surface 113 and the first plate surface 43 may be spacedapart from each other or in contact with each other.

As shown in FIG. 4, the rotating body tube 61 is inserted in the fixedbody insertion holes 91 and 111 so that the fixed bodies 90 and 110support the rotating body 60.

Specifically, the front rotating body end 61 a of the rotating body tube61 is inserted in the front fixed body insertion hole 91 and extendsthrough the front fixed body 90.

The front fixed body insertion hole 91 is shaped and sized correspondingto the rotating body tube 61 (specifically, the tube outercircumferential surface 62). In the present embodiment, the front fixedbody insertion hole 91 is circular as viewed in the axial direction Zcorresponding to the circular rotating body tube 61. The front fixedbody insertion hole 91 is equal to or slightly larger than the tubeouter circumferential surface 62 in diameter. The front rotating bodyend 61 a is supported by a front rotating body bearing 94, which isprovided in the inner wall surface defining the front fixed bodyinsertion hole 91, so as to be rotatable relative to the front fixedbody 90.

Likewise, the rear rotating body end 61 b is inserted in the rear fixedbody insertion hole 111 and extends through the rear fixed body 110.

The rear fixed body insertion hole 111 is shaped and sized correspondingto the rotating body tube 61 (specifically, the tube outercircumferential surface 62). In the present embodiment, the rear fixedbody insertion hole 111 is circular as viewed in the axial direction Zcorresponding to the circular rotating body tube 61. The rear fixed bodyinsertion hole 111 is equal to or slightly larger than the tube outercircumferential surface 62 in diameter. The rear rotating body end 61 bis supported by a rear rotating body bearing 114, which is provided inthe inner wall surface defining the rear fixed body insertion hole 111,so as to be rotatable relative to the rear fixed body 110.

The two fixed bodies 90 and 110 support the rotating body ends 61 a and61 b through the two rotating body bearings 94 and 114. The fixed bodies90 and 110 thus support the rotating body 60 and limit displacement ofthe rotating body 60 relative to the two fixed bodies 90 and 110.

Further, the two rotating body ends 61 a and 61 b are the axial ends ofthe rotating body 60, so that the rotating body bearings 94 and 114support the axial ends of the rotating body 60. The rotating body 60 isthus supported in a stable manner.

Further, the fixed body insertion holes 91 and 111 providedcorresponding to the rotating body tube 61 reduce or eliminate a gapprovided between the tube outer circumferential surface 62 and the innerwall surfaces defining the fixed body insertion holes 91 and 111.

Each rotating body bearing 94, 114 may be a coating bearing formed by acoating layer on the inner wall surface defining the fixed bodyinsertion hole 91, 111. FIG. 4 shows the rotating body bearing 94, 114thicker than the actual size. The rotating body bearing 94, 114 does nothave to be a coating bearing, and may be other sliding bearings orrolling bearings.

The front fixed body 90 has a front fixed body surface 100, which is afixed body surface facing the front rotating body surface 71 in theaxial direction Z. The front fixed body surface 100 is a plate surfaceopposite to the front back surface 93. The front fixed body surface 100is ring-shaped, and annular as viewed in the axial direction Z in thepresent embodiment.

As shown in FIG. 3, the front fixed body surface 100 includes a firstfront flat surface 101, a second front flat surface 102, and two frontcurved surfaces 103. The first and second front flat surfaces 101 and102 intersect with the axial direction Z (at right angles in the presentembodiment). The front curved surfaces 103 connect the two front flatsurfaces 101 and 102.

As shown in FIG. 4, the two front flat surfaces 101 and 102 aredisplaced from each other in the axial direction Z. Specifically, thesecond front flat surface 102, which serves as a fixed body contactsurface, is closer to the front rotating body surface 71 than the firstfront flat surface 101 and is in contact with the front rotating bodysurface 71. The section of the front fixed body surface 100 other thanthe second front flat surface 102 is spaced apart from the frontrotating body surface 71.

The two front flat surfaces 101 and 102 are spaced apart in thecircumferential direction of the front fixed body 90, and are displacedfrom each other by 180°, for example. In the present embodiment, eachfront flat surface 101, 102 has the shape of a sector. In the followingdescriptions, the circumferential positions in the fixed bodies 90 and110 are also referred to as angular positions.

Each of the two front curved surfaces 103 has the shape of a sector. Asshown in FIG. 3, the two front curved surfaces 103 are aligned in theradial direction as viewed in the axial direction Z. The two frontcurved surfaces 103 have the same shape.

Each front curved surface 103 connects the two front flat surfaces 101and 102. Specifically, one of the front curved surfaces 103 connects thefirst ends in the circumferential direction of the front flat surfaces101 and 102, and the other front curved surface 103 connects the secondends in the circumferential direction of the front flat surfaces 101 and102.

The angular positions of the borders between the first front flatsurface 101 and the front curved surfaces 103 are defined as firstangular positions θ1, and the angular positions of the borders betweenthe second front flat surface 102 and the front curved surfaces 103 aredefined as second angular positions θ2. Although the angular positionsθ1 and θ2 are indicated by broken lines in FIG. 3, the front curvedsurfaces 103 and the front flat surfaces 101 and 102 are actuallyconnected smoothly at the borders.

The position in the axial direction Z of each front curved surface 103varies with circumferential position, in other words, the angularposition in the front fixed body 90. Specifically, each front curvedsurface 103 is curved in the axial direction Z such that the distance tothe front rotating body surface 71 gradually decreases from the firstangular position θ1 to the second angular position θ2. In other words,the two front curved surfaces 103 are located on the opposite sides ofthe second front flat surface 102 in the circumferential direction andcurved in the axial direction Z such that the distance to the frontrotating body surface 71 gradually increases as the front curvedsurfaces 103 extend away from the second front flat surface 102 in thecircumferential direction.

Each front curved surface 103 includes a front concave surface 103 a,which is curved in the axial direction Z away from the front rotatingbody surface 71, and a front convex surface 103 b, which is curved inthe axial direction Z toward the front rotating body surface 71.

The front concave surface 103 a is closer to the first front flatsurface 101 than to the second front flat surface 102, and the frontconvex surface 103 b is closer to the second front flat surface 102 thanto the first front flat surface 101. The front concave surface 103 a iscontinuous with the front convex surface 103 b. That is, the frontcurved surface 103 has an inflection point.

The angular range of the front convex surface 103 b and the angularrange of the front concave surface 103 a may be the same or different.Further, the position of the inflection point is arbitrary. Since thefront curved surface 103 is curved in a wave shape, the front fixed bodysurface 100 may be considered as a front wavy surface including sectionsthat are curved in a wave shape.

The rear fixed body 110 has a rear fixed body surface 120, which is afixed body surface facing the rear rotating body surface 72 in the axialdirection Z. The rear fixed body surface 120 is a plate surface oppositeto the rear back surface 113. The rear fixed body surface 120 isring-shaped, and annular as viewed in the axial direction Z in thepresent embodiment.

In the present embodiment, the rear fixed body surface 120 has the sameshape as the front fixed body surface 100. As shown in FIG. 2, the rearfixed body surface 120 includes a first rear flat surface 121, a secondrear flat surface 122, and two rear curved surfaces 123. The first andsecond rear flat surfaces 121 and 122 intersect with the axial directionZ (at right angles in the present embodiment). The rear curved surfaces123 connect the two rear flat surfaces 121 and 122.

As shown in FIG. 4, the two rear flat surfaces 121 and 122 are displacedfrom each other in the axial direction Z. Specifically, the second rearflat surface 122, which serves as a fixed body contact surface, iscloser to the rear rotating body surface 72 than the first rear flatsurface 121 and is in contact with the rear rotating body surface 72.The section of the rear fixed body surface 120 other than the secondrear flat surface 122 is spaced apart from the rear rotating bodysurface 72.

The two rear flat surfaces 121 and 122 are spaced apart from each otherin the circumferential direction of the rear fixed body 110, and aredisplaced from each other by 180°, for example. In the presentembodiment, each rear flat surface 121, 122 has the shape of a sector.

Each of the two rear curved surfaces 123 has the shape of a sector. Thetwo rear curved surfaces 123 face each other in the radial direction asviewed in the axial direction Z. One of the rear curved surfaces 123connects the first ends in the circumferential direction of the rearflat surfaces 121 and 122, and the other rear curved surface 123connects the second ends in the circumferential direction of the rearflat surfaces 121 and 122.

The two rear curved surfaces 123 are arranged on the opposite sides ofthe second rear flat surface 122 in the circumferential direction andcurved in the axial direction Z such that the distance to the rearrotating body surface 72 gradually increases as the curved surfaces 123extend away from the second rear flat surface 122 in the circumferentialdirection.

The two fixed body surfaces 100 and 120 face toward each other in theaxial direction Z with the rotating body ring 70 placed between them. Inaddition, the two fixed body surfaces 100 and 120 are arranged inangular positions that are different from each other by 180°.

The distance between the two fixed body surfaces 100 and 120 in theaxial direction Z is uniform at any angular positions (i.e., thecircumferential positions). Specifically, as shown in FIG. 4, the firstfront flat surface 101 and the second rear flat surface 122 face eachother in the axial direction Z, and the second front flat surface 102and the first rear flat surface 121 face each other in the axialdirection Z. The displacement in the axial direction Z between the twofront flat surfaces 101 and 102 is equal to the displacement between thetwo rear flat surfaces 121 and 122. Hereinafter, the displacement in theaxial direction Z between the two front flat surfaces 101 and 102 andthe displacement between the two rear flat surfaces 121 and 122 aresimply referred to as displacement Z1.

Further, the front curved surfaces 103 and the rear curved surfaces 123have the same curvatures. That is, the front curved surfaces 103 and therear curved surfaces 123 are curved in the same manner so that thedistance in the axial direction Z does not vary with the angularposition. The distance between the two fixed body surfaces 100 and 120in the axial direction Z is therefore uniform at any angular positions.

The shapes of the first rear flat surface 121, the second rear flatsurface 122, and the two rear curved surfaces 123 are the same as thoseof the first front flat surface 101, the second front flat surface 102,and the two front curved surfaces 103 and thus not described in detail.As with the front curved surface 103, since the rear curved surface 123is curved in a wave shape, the rear fixed body surface 120 may beconsidered as a rear wavy surface including sections that are curved ina wave shape.

The circumferential direction of the two fixed bodies 90 and 110 and therotating body 60 is the same as the circumferential direction of therotary shaft 12. The radial direction of the two fixed bodies 90 and 110and the rotating body 60 is the same as the radial direction R of therotary shaft 12. The axial direction of the fixed bodies 90 and 110 andthe rotating body 60 is the same as the axial direction Z of the rotaryshaft 12. As such, the circumferential direction, the radial directionR, and the axial direction Z of the rotary shaft 12 are interchangeablewith those of the rotating body 60 and the fixed bodies 90 and 110.

As shown in FIG. 4, the compressor 10 includes compression chambers A4and A5, in which suction and compression of the fluid are performed. Thecompression chambers A4 and A5 are provided in the accommodation chamberA3, specifically, on the opposite sides of the rotating body ring 70 inthe axial direction Z.

The front compression chamber A4 is defined by the front rotating bodysurface 71 and the front fixed body surface 100, more specifically, bythe front rotating body surface 71, the front fixed body surface 100,the tube outer circumferential surface 62, and the front cylinder innercircumferential surface 33.

The rear compression chamber A5 is defined by the rear rotating bodysurface 72 and the rear fixed body surface 120, more specifically, bythe rear rotating body surface 72, the rear fixed body surface 120, thetube outer circumferential surface 62, and the front cylinder innercircumferential surface 33. In the present embodiment, the frontcompression chamber A4 and the rear compression chamber A5 are equal insize.

The compression chambers A4 and A5 face the discharge chamber A1 in theradial direction R with the front cylinder circumferential wall 32located between them. That is, the discharge chamber A1 is located onthe outer side of the compression chambers A4 and A5 in the radialdirection R.

In the present embodiment, the discharge chamber A1 faces a part of thefront compression chamber A4 in the radial direction R, and faces theentire rear compression chamber A5 in the radial direction R. However,the present disclosure is not limited to this configuration. Anyconfiguration may be used as long as the discharge chamber A1 extends inthe axial direction Z so as to face at least a part of the frontcompression chamber A4 and at least a part of the rear compressionchamber A5 in the radial direction R.

As shown in FIGS. 2 to 5, the compressor 10 includes multiple (three)vane grooves 130 provided in the rotating body 60 and multiple (three)vanes 131 inserted in the respective vane grooves 130.

The vane grooves 130 are provided in the rotating body ring 70. The vanegrooves 130 extend through the rotating body ring 70 in the axialdirection Z and open at the two rotating body surfaces 71 and 72. Eachvane groove 130 extends in the radial direction R, has a width in adirection orthogonal to both of the axial direction Z and the radialdirection R, and opens radially outward. The rotating body tube 61 doesnot have a vane groove 130. Each vane groove 130 has two side surfacesthat face each other and are spaced apart from each other in thecircumferential direction.

The rotating body ring 70 is a section positioned radially outward fromthe rotating body tube 61. As such, the rotating body tube 61 is locatedradially inward from the rotating body ring 70. That is, the rotatingbody ring 70 is a section that is positioned on the tube outercircumferential surface 62 and protrudes radially outward from the tubeouter circumferential surface 62.

Each vane 131 is generally a rectangular plate having plate surfacesthat intersect with (extend orthogonal to) the circumferential directionof the rotary shaft 12. The vane 131 is located between the two fixedbodies 90 and 110 (i.e., the two fixed body surfaces 100 and 120). Thevane 131 is a plate having a thickness in the width direction of thevane groove 130, in other words, in a direction orthogonal to both ofthe axial direction Z and the radial direction R.

The two plate surfaces of the vane 131 face the respective side surfacesof the vane groove 130 in the circumferential direction (i.e., the widthdirection of the vane groove 130). The width of the vane groove 130(i.e., the distance between the two side surfaces of the vane groove130) is the same as or slightly wider than the plate thickness of thevane 131. The vane 131 inserted in the vane groove 130 is sandwichedbetween the two side surfaces of the vane groove 130. The vane 131 canmove in the axial direction Z along the vane groove 130. In the presentembodiment, the vane 131, specifically, the two axial ends of the vane131, is in contact with the fixed body surfaces 100 and 120.

The vane grooves 130 are arranged at regular intervals in thecircumferential direction, specifically, at intervals of 120°. The vanes131 are arranged accordingly at regular intervals in the circumferentialdirection.

Rotation of the rotating body 60 rotates the vanes 131 in the rotationdirection M. At the same time, the vanes 131, which are in contact withthe fixed body surfaces 100 and 120, move (swing) in the axial directionZ along the curved fixed body surfaces 100 and 120. That is, the vanes131 rotate while moving in the axial direction Z. As a result, the vanes131 move into the front compression chamber A4 and the rear compressionchamber A5. That is, the vane grooves 130 rotate and place the vanes 131in the compression chambers A4 and A5 as the rotating body 60 rotates.

The moving distance (in other words, the swinging distance) of the vanes131 in the axial direction Z is the difference between the positions ofthe front flat surfaces 101 and 102 (or between the rear flat surfaces121 and 122) in the axial direction Z, that is, the displacement Z1. Thevanes 131 are continuously in contact with the two fixed body surfaces100 and 120 while the rotating body 60 rotates. The vanes 131 are thusunlikely to intermittently come into contact, or more specifically, comeinto and out of contact repeatedly, with the fixed body surfaces 100 and120.

As shown in FIG. 6, the three vanes 131 partition the front compressionchamber A4 into three part chambers, a first front compression chamberA4 a, a second front compression chamber A4 b, and a third frontcompression chamber A4 c.

For convenience of description, of the three part chambers, the partchamber located on the leading side of the second front flat surface 102in the rotation direction M is referred to as the first frontcompression chamber A4 a.

Of the three part chambers, the part chamber located on the trailingside of the first front compression chamber A4 a in the rotationdirection M is referred to as the second front compression chamber A4 b.At least a part of the second front compression chamber A4 b is locatedon the trailing side of the second front flat surface 102 in therotation direction M.

Of the three part chambers, the part chamber located between the firstfront compression chamber A4 a and the second front compression chamberA4 b in the circumferential direction is referred to as the third frontcompression chamber A4 c. In the rotation direction M, the third frontcompression chamber A4 c is located on the leading side of the firstfront compression chamber A4 a and located on the trailing side of thesecond front compression chamber A4 b.

In the following description, the leading side in the rotation directionM and the trailing side in the rotation direction M may simply bereferred to as the leading side and the trailing side, respectively.

Each of the front compression chambers A4 a to A4 c spans over anangular range of 120°. That is, each of the front compression chambersA4 a to A4 c extends in the circumferential direction, and the length ofeach chamber in the circumferential direction corresponds to an angularrange of 120°.

Specifically, when one of the vanes 131 is in contact with the secondfront flat surface 102, this vane 131 is not positioned within the frontcompression chamber A4. At this time, the spaces at opposite sides inthe circumferential direction of the vane 131 that is in contact withthe second front flat surface 102 are separated from each other by thesection where the front rotating body surface 71 is in contact with thesecond front flat surface 102. The spaces are not continuous with eachother. Thus, even when one of the vanes 131 is in contact with thesecond front flat surface 102, the front compression chamber A4 ispartitioned into three part chambers. In the present embodiment, forconvenience of description, even when one of the vanes 131 is in contactwith the second front flat surface 102, the front compression chamber A4is considered to be partitioned by the three vanes 131 into the frontcompression chambers A4 a to A4 c.

As shown in FIG. 7, in the same manner as the front compression chamberA4, the three vanes 131 partition the rear compression chamber A5 into afirst rear compression chamber A5 a, a second rear compression chamberA5 b, which is on the trailing side of the first rear compressionchamber A5 a, and a third rear compression chamber A5 c located betweenthe first rear compression chamber A5 a and the second rear compressionchamber A5 b in the circumferential direction. The first to third rearcompression chambers A5 a, A5 b and A5 c are the same as the first tothird front compression chambers A4 a, A4 b and A4 c and thus notdescribed in detail.

The configuration relating to the suction of fluid into the compressionchambers A4 and A5 and the discharging of compressed fluid will now bedescribed. FIG. 4 schematically shows a front suction port 141 and arear suction port 142.

As shown in FIGS. 2 to 4 and 6, the compressor 10 includes a frontsuction port 141 through which fluid is drawn into the front compressionchamber A4. The front suction port 141 may be provided in the frontcylinder 30. Specifically, the front suction port 141 extends in thefront cylinder end wall 31 and the front cylinder circumferential wall32 in the axial direction Z.

In addition, the front suction port 141 extends in the circumferentialdirection along the front cylinder circumferential wall 32 and is formedin an arc shape as viewed in the axial direction Z. At least a part ofthe front suction port 141 is located radially outward from the firstfront compression chamber A4 a. In other words, the first frontcompression chamber A4 a includes a part of or the entire cavity locatedradially inward from the front suction port 141.

The front suction port 141 opens to the motor chamber A2 and also to thefront compression chamber A4. The front suction port 141 thus connectsthe motor chamber A2 and the front compression chamber A4 to each other.

Specifically, as shown in FIG. 6, the front suction port 141 has a frontsuction opening 141 a, which is positioned to be continuous with thefirst front compression chamber A4 a. The front suction opening 141 aextends in the front cylinder inner circumferential surface 33 in therotation direction M from a position corresponding to thecircumferential center of the second front flat surface 102. Theextending length of the front suction opening 141 a may be substantiallythe same as the circumferential length of each of the front compressionchambers A4 a to A4 c, for example. That is, the front suction opening141 a may extend in the front cylinder inner circumferential surface 33in the circumferential direction from a position corresponding to thecircumferential center of the second front flat surface 102 bysubstantially the same length as the circumferential interval betweenthe vanes 131.

When the angular position of the circumferential center of the secondfront flat surface 102 is defined as 0° and the angle increases fromthis 0° angular position in the rotation direction M, the front suctionopening 141 a preferably extends at least from the leading edge in therotation direction M of the second front flat surface 102 to the 120°angular position.

As shown in FIGS. 6 and 8, the compressor 10 includes front dischargeports 151, which discharge the fluid compressed in the front compressionchamber A4, a front valve 152, which opens and closes the frontdischarge ports 151, and a front retainer 153, which adjusts the openingdegree of the front valve 152.

As shown in FIG. 6, the front discharge ports 151 may be placed in aposition of the front cylinder circumferential wall 32 that is radiallyoutward from the front compression chamber A4 and on the trailing sideof the second front flat surface 102.

Specifically, the curved front cylinder outer circumferential surface 34has a front seat surface 154, which is a recessed surface in the frontcylinder outer circumferential surface 34. The front seat surface 154 isprovided in a section of the front cylinder outer circumferentialsurface 34 that is located between the front compression chamber A4 andthe discharge chamber A1 and on the trailing side of the second frontflat surface 102. The front seat surface 154 is a flat surface extendingorthogonal to the radial direction R.

As shown in FIG. 6, the front discharge ports 151 are provided in thefront seat surface 154. The front discharge ports 151 extend through thefront cylinder circumferential wall 32 in the radial direction R,thereby connecting the second front compression chamber A4 b and thedischarge chamber A1 to each other.

The front discharge ports 151 are arranged in the circumferentialdirection. Each front discharge port 151 is circular. However, thenumber and shape of the front discharge ports 151 may be changed. Forexample, the front seat surface 154 may include only one front dischargeport 151. The front discharge port 151 may be oval. When front dischargeports 151 are provided, the sizes of the front discharge ports 151 maybe the same or different from one another.

At least a part of each front discharge port 151 is located radiallyoutward from the second front compression chamber A4 b. In other words,the second front compression chamber A4 b includes a part of or theentire cavity located radially inward from the front discharge ports151.

The front suction port 141 and the front discharge ports 151 are spacedapart from each other in the circumferential direction. A section of thefront cylinder circumferential wall 32 that is located radially outwardfrom the second front flat surface 102 is present between these ports141 and 151.

That is, the first front compression chamber A4 a is configured to becontinuous with the front suction port 141 but not with the frontdischarge ports 151.

The second front compression chamber A4 b is continuous with the frontdischarge ports 151. However, since the second front compression chamberA4 b has a longer circumferential length than the second front flatsurface 102, depending on the angular position of the vanes 131, thesecond front compression chamber A4 b may be located radially inwardfrom the front suction port 141 and radially inward from the frontdischarge ports 151 simultaneously. Nevertheless, in the presentembodiment, the area of contact between the front rotating body surface71 and the second front flat surface 102 is present between the spaceradially inward from the front suction port 141 and the space radiallyinward from the front discharge ports 151. As such, regardless of theangular position of the vanes 131, this contact area disconnects thesetwo spaces from each other. Thus, the front suction port 141 is notcontinuous with the front discharge ports 151. That is, the contact areapartitions the second front compression chamber A4 b further into aspace for suction and a space for compression.

As the rotating body 60 rotates, the third front compression chamber A4c moves from a position where the chamber A4 c is not continuous withthe front discharge ports 151 to a position where it is continuous withthe front discharge ports 151.

As shown in FIG. 8, the front valve 152 and the front retainer 153 areprovided on the front seat surface 154. The front seat surface 154 hasscrew holes 154 a. The front valve 152 and the front retainer 153 arefixed to the front seat surface 154 by bolts B, which extend through thefront retainer 153 and the front valve 152 and engage the screw holes154 a.

The front valve 152 normally closes the front discharge ports 151. Whenthe pressure in the front compression chamber A4 (specifically, thesecond front compression chamber A4 b) exceeds the threshold, the frontvalve 152 moves from a position that closes the front discharge ports151 to a position that opens the front discharge ports 151. The fluidcompressed in the front compression chamber A4 is thus discharged intothe discharge chamber A1. The front retainer 153 limits the openingangle of the front valve 152.

As shown in FIGS. 2 to 4 and 7, the compressor 10 includes a rearsuction port 142 through which the fluid is drawn into the rearcompression chamber A5. The rear suction port 142 may be formed in thefront cylinder 30. Specifically, the rear suction port 142 extends inthe front cylinder end wall 31 and the front cylinder circumferentialwall 32 in the axial direction Z.

In addition, the rear suction port 142 extends in the circumferentialdirection along the front cylinder circumferential wall 32 and is formedin an arc shape as viewed in the axial direction Z. At least a part ofthe rear suction port 142 is located radially outward from the firstrear compression chamber A5 a. In other words, the first rearcompression chamber A5 a includes a part of or the entire cavity locatedradially inward from the rear suction port 142.

The rear suction port 142 opens to the motor chamber A2 and also to therear compression chamber A5. The rear suction port 142 thus connects themotor chamber A2 and the rear compression chamber A5 to each other.

Specifically, as shown in FIG. 7, the rear suction port 142 has a rearsuction opening 142 a, which is positioned to be continuous with thefirst rear compression chamber A5 a. The rear suction opening 142 aextends in the front cylinder inner circumferential surface 33 in therotation direction M from a position corresponding to thecircumferential center of the second rear flat surface 122.

The rear suction port 142 and the rear suction opening 142 a extend inthe rotation direction M from the position corresponding to thecircumferential center of the second rear flat surface 122 to an extentthat does not interferes with the front discharge ports 151, the frontvalve 152, or the front retainer 153.

However, the present disclosure is not limited to this, and the rearsuction port 142 and the rear suction opening 142 a may have the samecircumferential length as the front suction port 141 and the frontsuction opening 141 a. In this case, to prevent the rear suction port142 and the rear suction opening 142 a from interfering with the frontdischarge ports 151 or other parts, the axial length of the front valve152 may be shortened, the front discharge ports 151 may be displaced, orthe angular range of the second front flat surface 102 may be reduced.

The present embodiment has two suction ports 141 and 142 correspondingto the two compression chambers A4 and A5. The front suction port 141and the rear suction port 142 are displaced from each other in thecircumferential direction so as not to be continuous with each other.Specifically, these ports 141 and 142 are displaced from each other by180°. As a result, the suction of fluid into one of the compressionchambers A4 and A5 is less likely to reduce the amount of the fluiddrawn into the other compression chamber, which would otherwise occur ifthe two suction ports 141 and 142 are continuous with each other.

As shown in FIG. 7, the compressor 10 includes rear discharge ports 161,which discharge the fluid compressed in the rear compression chamber A5,a rear valve 162, which opens and closes the rear discharge ports 161,and a rear retainer 163, which adjusts the opening degree of the rearvalve 162.

The rear discharge ports 161 may be placed in a position of the frontcylinder circumferential wall 32 that is radially outward from the rearcompression chamber A5 and on the trailing side of the second rear flatsurface 122.

In accordance with the second front flat surface 102 and the second rearflat surface 122, which are displaced from each other by 180°, the reardischarge ports 161 are displaced from the front discharge ports 151 by180° in the circumferential direction. Further, in accordance with thefront compression chamber A4 and the rear compression chamber A5, whichare displaced from each other in the axial direction Z, the reardischarge ports 161 are displaced from the front discharge ports 151 inthe axial direction Z.

The specific configurations of the rear discharge ports 161, the rearvalve 162, and the rear retainer 163 are substantially the same as thoseof the front discharge ports 151, the front valve 152, and the frontretainer 153 except for their positions, and thus not described indetail. The term “front” in the description of the front discharge ports151, the front valve 152, and the front retainer 153 may be replacedwith “rear.” The discharge ports 151 and 161 may be considered asdischarge passages.

The vanes 131 will now be described. In the following description, ofthe two part chambers separated by a vane 131, the part chamber on thetrailing side of the vane 131 is referred to as a first part chamber Ax,and the part chamber located on the leading side of the vane 131 isreferred to as a second part chamber Ay. For the vane 131 separating thefirst front compression chamber A4 a from the third front compressionchamber A4 c, the first part chamber Ax is the first front compressionchamber A4 a, and the second part chamber Ay is the third frontcompression chamber A4 c. For the vane 131 separating the third frontcompression chamber A4 c from the second front compression chamber A4 b,the first part chamber Ax is the third front compression chamber A4 c,and the second part chamber Ay is the second front compression chamberA4 b. For the vane 131 separating the second front compression chamberA4 b from the first front compression chamber A4 a, the first partchamber Ax is the second front compression chamber A4 b, and the secondpart chamber Ay is the first front compression chamber A4 a. The sameapplies to the rear compression chamber A5.

The pressure in each of the front compression chambers A4 a to A4 ctends to be higher if the chamber is located on the leading side in therotation direction M. Specifically, the pressure tends to be the highestin the second front compression chamber A4 b (in particular, the spaceon the trailing side of the area of contact between the front rotatingbody surface 71 and the second front flat surface 102), followed by thethird front compression chamber A4 c and the first front compressionchamber A4 a. For this reason, the pressure of the second part chamberAy on the leading side of a vane 131 tends to be higher than thepressure of the first part chamber Ax on the trailing side of the vane131.

As shown in FIGS. 9 to 13, each vane 131 consists of multiple parts.Specifically, the vane 131 includes a vane body 170, which is insertedin a vane groove 130, and two tip seals 180 and 190, which are arrangedon the opposite end faces 171, 172 in the axial direction Z of the vanebody 170. The tip seals 180 and 190 form the axial ends of the vane 131and are in contact with the fixed body surfaces 100 and 120,respectively.

The vane body 170 is made of the same material as the rotating body 60and the fixed bodies 90 and 110. In one example, the vane body 170 ismade of metal. The vane body 170 is planar and inserted in a vane groove130 with its thickness direction extending in the width direction of thevane groove 130. The vane body 170 extends in the axial direction Z andthe radial direction R. The vane body 170 is a rectangular plate in thepresent embodiment, but the vane body 170 may be a plate of any shape.The vane body 170 is received in the vane groove 130 regardless of themovement of the vane 131 in the axial direction Z.

The vane body 170 has two end faces 171 and 172 including bodyattachment grooves 173 and 174, respectively, which serve as bodyattachment sections. The body attachment grooves 173 and 174 have awidth in the thickness direction of the vane 131, extend in the radialdirection R, and open to the inner and outer sides in the radialdirection R.

Each body attachment groove 173, 174 has a body groove bottom surface173 a, 174 a and a first body groove side surface 173 b, 174 b and asecond body groove side surface 173 c, 174 c, which extend from the bodygroove bottom surface 173 a, 174 a. The first body groove side surface173 b, 174 b and the second body groove side surface 173 c, 174 cintersect with the circumferential direction (in other words, adirection orthogonal to both of the axial direction Z and the radialdirection R). These two surfaces face each other and spaced apart fromeach other in the circumferential direction. The second body groove sidesurface 173 c, 174 c is on the leading side of the first body grooveside surface 173 b, 174 b in the rotation direction M. That is, thefirst body groove side surface 173 b, 174 b is the side surface on thetrailing side of the body attachment groove 173, 174, and the secondbody groove side surface 173 c, 174 c is the side surface on the leadingside of the body attachment groove 173, 174.

The tip seals 180 and 190 are made of a material that differs from thematerial of the vane body 170, such as a material that is easier todeform (i.e., softer) than the vane body 170. For example, the tip seals180 and 190 are made from resin. Each tip seal 180, 190 is in contactwith the fixed body surface 100, 120, so that the two part chambers Axand Ay on the opposite sides in the circumferential direction of thevane 131 are not continuous with each other. In this embodiment, the twotip seals 180 and 190 have the same shape. The areas of contact betweenthe tip seals 180 and 190 and the fixed body surfaces 100 and 120 arereferred to as distal end contact areas Pa1 and Pa2, respectively.

As shown in FIGS. 9 to 11, the tip seal 180, 190 may be elongated andextend in the radial direction R. Each tip seal 180, 190 may include aseal body 181, 191, which is in contact with the fixed body surface 100,120, and a seal attachment protrusion 182, 192, which serves as a sealattachment section attached to the vane body 170.

As shown in FIG. 12, each seal body 181, 191 has a width that issubstantially the same as the thickness of the vane body 170 and issandwiched by the end face 171, 172 of the vane body 170 and the fixedbody surface 100, 120 in the axial direction Z. In other words, the sealbody 181, 191 is located between the end face 171, 172 of the vane body170 and the fixed body surface 100, 120.

As shown in FIGS. 11 and 12, each seal body 181, 191 includes a sealsurface 181 a, 191 a, which is a convex surface curved toward the fixedbody surface 100, 120, and a seal body bottom surface 181 b, 191 b,which faces the end face 171, 172 of the vane body 170 in the axialdirection Z.

The seal surface 181 a, 191 a faces the fixed body surface 100, 120 inthe axial direction Z. The seal surface 181 a, 191 a is in contact withthe fixed body surface 100, 120. The curvature of the seal surface 181a, 191 a is flatter than that of a configuration in which the seal body181, 191 is semicircular. Specifically, the curvature radius of the sealsurface 181 a, 191 a is greater than half the thickness of the vane 131.However, the present disclosure is not limited to this, and the sealsurface 181 a, 191 a may have any curvature.

The seal surface 181 a, 191 a extends in the radial direction R and isin contact with the fixed body surface 100, 120 along its entire lengthin the radial direction R. However, the present disclosure is notlimited to this, and the seal body 181, 191 may be in contact with thefixed body surface 100, 120 only partially along its length in theradial direction R.

Each seal attachment protrusion 182, 192 is a ridge that protrudes fromthe seal body 181, 191 toward the vane body 170, has a width in thethickness direction of the vane 131, and extends in the radial directionR. The seal attachment protrusion 182, 192 includes an attachment distalend face 182 a, 192 a, a first seal protrusion side surface 182 b, 192b, and a second seal protrusion side surface 182 c, 192 c located on theleading side of the first seal protrusion side surface 182 b, 192 b. Thefirst seal protrusion side surface 182 b, 192 b and the second sealprotrusion side surface 182 c, 192 c intersect with the circumferentialdirection. The first seal protrusion side surface 182 b, 192 b is theside surface on the trailing side of the seal attachment protrusion 182,192, and the second seal protrusion side surface 182 c, 192 c is theside surface on the leading side of the seal attachment protrusion 182,192.

The seal attachment protrusion 182, 192 is inserted in the bodyattachment groove 173, 174 so that the tip seal 180, 190 is attached tothe vane body 170. The body attachment groove 173, 174, which is a bodyattachment section, and the seal attachment protrusion 182, 192 faceeach other in the circumferential direction (i.e., the width directionof the vane groove 130). Specifically, the first body groove sidesurface 173 b, 174 b and the first seal protrusion side surface 182 b,192 b face each other in the circumferential direction, and the secondbody groove side surface 173 c, 174 c and the second seal protrusionside surface 182 c, 192 c face each other in the circumferentialdirection. The tip seals 180 and 190 can move toward and away from thevane body 170 in the axial direction Z. That is, the tip seals 180 and190 are attached to the vane body 170 so as to be movable in the axialdirection Z relative to the vane body 170.

The tip seals 180 and 190 are movable in the axial direction Z relativeto the vane body 170, and the vane 131 includes the vane body 170 andthe tip seals 180 and 190. As such, the vane 131 may be considered asextendable in the axial direction Z.

As shown in FIGS. 11 and 12, a back pressure space 183, 193, which isprovided between the vane body 170 and the tip seal 180, 190, pushes thetip seal 180, 190 toward the fixed body surface 100, 120.

The front back pressure space 183 is defined by the front attachmentdistal end face 182 a, the front body groove bottom surface 173 a, thefront first body groove side surface 173 b, and the front second bodygroove side surface 173 c. The width of the front seal attachmentprotrusion 182 is the same as or slightly smaller than the width of thefront body attachment groove 173. Thus, the gap between the front sealattachment protrusion 182 and the front body attachment groove 173allows the fluid to enter the front back pressure space 183. The sameapplies to the rear back pressure space 193.

As shown in FIGS. 11 and 12, the compressor 10 has introduction grooves184 and 194 that introduce the fluid into the back pressure spaces 183and 193 from the second part chamber Ay.

Each tip seal 180, 190 has introduction grooves 184, 194. The tip seal180, 190 includes multiple (two in this embodiment) introduction grooves184, 194, which are spaced apart from each other in the radial directionR. However, the number of the introduction grooves 184, 194 isarbitrary, and may be one or three or more.

As shown in FIG. 12, the introduction grooves 184, 194 extend along theseal body 181, 191 and the seal attachment protrusion 182, 192.Specifically, each introduction groove 184, 194 extends along the secondseal protrusion side surface 182 c, 192 c and a section of the seal bodybottom surface 181 b, 191 b located on the leading side of the sealattachment protrusion 182, 192.

Each front introduction groove 184 is provided on the leading side ofthe front tip seal 180 and opens to the second part chamber Ay, which islocated on the leading side. Likewise, each rear introduction groove 194is provided on the leading side of the rear tip seal 190 and opens tothe second part chamber Ay. This allows the fluid in the second partchamber Ay to flow easily into the back pressure spaces 183 and 193through the introduction grooves 184 and 194.

In this configuration, the fluid in each back pressure space 183, 193pushes the tip seal 180, 190 toward the fixed body surface 100, 120,reducing the likelihood of a gap created between the tip seal 180, 190and the fixed body surface 100, 120.

Specifically, even in a configuration in which the rotating body 60 issupported by the two fixed bodies 90 and 110 with the rotating body tube61, dimensional or assembly errors in the manufacturing of the rotatingbody 60 and the fixed bodies 90 and 110 can result in a gap createdbetween a vane 131 and at least one of the two fixed body surfaces 100and 120. Such a gap can be created over the entire angular range inwhich the vane 131 rotates, or only in a specific angular range.

In the present embodiment, as shown in FIG. 12, when the vane bodies 170rotate together with the rotating body 60, the vane bodies 170 push thetip seals 180 and 190 in the rotation direction M. This brings eachfirst seal protrusion side surface 182 b, 192 b, which is the sidesurface on the trailing side of the seal attachment protrusion 182, 192,into contact with the first body groove side surface 173 b, 174 b, whichis the side surface on the trailing side of the body attachment groove173, 174, in the circumferential direction. This area of contact(hereinafter referred to as a “side surface contact area Pb1, Pb2”)provides sealing, thereby reducing the possibility that the fluid movesthrough between each tip seal 180, 190 and the vane body 170 and thusbetween the two part chambers Ax and Ay.

In particular, each side surface contact area Pb1, Pb2 of the presentembodiment extends in the axial direction Z. This helps to maintain thecontact between the first seal protrusion side surface 182 b, 192 b andthe first body groove side surface 173 b, 174 b even when the tip seal180, 190 moves in the axial direction Z relative to the vane body 170.

Since the body attachment groove 173, 174 forms the body attachmentsection, the side surface contact area Pb1, Pb2 may be considered as anarea of contact between the body attachment section and the sealattachment protrusion 182, 192.

On the other hand, a clearance is provided on the leading side in therotation direction M. Specifically, a clearance is provided between eachsecond seal protrusion side surface 182 c, 192 c and the second bodygroove side surface 173 c, 174 c. As indicated by the long dasheddouble-short dashed lines in FIG. 12, the clearance introduces the fluidinto the back pressure space 183, 193 from the second part chamber Ay.In particular, in the present embodiment, the introduction grooves 184,194 facilitate the flow of fluid from the second part chamber Ay intothe back pressure space 183, 193.

The fluid flowing into the back pressure space 183, 193 pushes the tipseal 180, 190 toward the fixed body surface 100, 120. This maintains thecontact and thus the sealing between the tip seal 180, 190(specifically, the seal surface 181 a, 191 a) and the fixed body surface100, 120. A gap is therefore unlikely to be created between the tip seal180, 190 and the fixed body surface 100, 120.

The depth of the body attachment groove 173, 174 may be greater than theprotruding amount of the seal attachment protrusion 182, 192. Thismaintains the back pressure space 183, 193 even when the seal bodybottom surface 181 b, 191 b is in contact with the end face 171, 172,aspaceing the problem that the back pressure space 183, 193 disappears.However, the depth of the body attachment groove 173, 174 is not limitedto this, and may be less than or equal to the protruding amount of theseal attachment protrusion 182, 192.

As shown in FIGS. 9 and 13, each vane 131 includes a vane outer end face201 and a vane inner end face 202, which are the two end faces in theradial direction R. Of the two end faces in the radial direction R, thevane outer end face 201 is on the outer side in the radial direction R(located radially outward), and the vane inner end face 202 is on theinner side in the radial direction R (located radially inward).

The vane outer end face 201 includes the outer end face of the vane body170 and the outer end faces of the two tip seals 180 and 190. The outerend face of the vane body 170 and the outer end faces of the two tipseals 180 and 190 are continuous in the axial direction Z and flush withone another. The vane outer end face 201 is thus a single plane.

The vane outer end face 201 is in contact with the front cylinder innercircumferential surface 33 regardless of the movement of the vane 131.That is, the front cylinder inner circumferential surface 33 is longerin the axial direction Z than the moving range of the vane 131 so as tomaintain the contact with the vane outer end face 201 regardless of themovement of the vane 131.

As shown in FIG. 13, the vane outer end face 201 may be a convex surfacecurved radially outward so as to be continuous with the ring outercircumferential surface 73 in the circumferential direction. Thecurvature of the vane outer end face 201 is preferably the same as thatof the front cylinder inner circumferential surface 33. That is, thevane outer end face 201 is preferably in planar contact with the frontcylinder inner circumferential surface 33. However, the vane outer endface 201 may have other shapes.

In the same manner as the vane outer end face 201, each vane inner endface 202 includes the inner end face of the vane body 170 and the innerend faces of the two tip seals 180 and 190. The inner end face of thevane body 170 and the inner end faces of the two tip seals 180 and 190are continuous in the axial direction Z and flush with one another. Thevane inner end face 202 is thus a single plane.

As shown in FIG. 13, the vane inner end face 202 is a concave surfacecurved radially outward. The curvature of the vane inner end face 202 ispreferably the same as that of the tube outer circumferential surface62. That is, the vane inner end face 202 is preferably in planar contactwith the tube outer circumferential surface 62. However, the vane innerend face 202 may have other shapes.

Referring to FIGS. 14 and 15, the sequence of operations of thecompressor 10 will now be described. FIGS. 14 and 15 are developed viewsschematically showing the rotating body 60, the fixed bodies 90 and 110,and the vanes 131. FIGS. 14 and 15 show the rotating body 60 and thevanes 131 at different phases. The ports 141, 142, 151 and 161 are shownschematically in FIGS. 14 and 15.

As shown in FIGS. 14 and 15, when the electric motor 13 rotates therotary shaft 12, the rotating body 60 rotates accordingly. The vanes 131thus rotate while moving in the axial direction Z along the fixed bodysurfaces 100 and 120 and maintaining the positional relationship betweenone another in the circumferential direction. As viewed in FIGS. 14 and15, the vanes 131 move downward while moving in the left-rightdirection. This changes the volumes of the front compression chambers A4a to A4 c and the rear compression chambers A5 a to A5 c, allowing forsuction, compression and expansion of the fluid. That is, the rotationand movement in the axial direction Z of the vanes 131 perform thesuction and compression of fluid in the compression chambers A4 and A5.

Specifically, the first front compression chamber A4 a and the space inthe second front compression chamber A4 b that is located on the leadingside of the second front flat surface 102 increase in volume and performsuction of fluid through the front suction port 141.

In contrast, the third front compression chamber A4 c and the space inthe second front compression chamber A4 b that is located on thetrailing side of the second front flat surface 102 (the trailing space)decrease in volume as the rotating body 60 rotates and performcompression of the fluid. Specifically, the fluid is compressed in thethird front compression chamber A4 c, and the fluid compressed in thethird front compression chamber A4 c is further compressed in thetrailing space of the second front compression chamber A4 b.

When the pressure in the trailing space of the second front compressionchamber A4 b exceeds the threshold, the front valve 152 opens allowingthe fluid compressed in the second front compression chamber A4 b to bedischarged into the discharge chamber A1 through the front dischargeports 151. The same applies to the rear compression chamber A5.

As described above, the rotation of the rotating body 60 and the vanes131 results in one cycle of suction and compression, which correspondsto 480°, repeated in the three part chambers in each of the compressionchambers A4 and A5. Specifically, in each compression chamber A4, A5,the fluid is drawn and expanded in the phase between 0° and 240°, andthe fluid is compressed in the phase between 240° and 480°.

For example, it is assumed that the angular position of thecircumferential center of the second front flat surface 102 is 0°, andthe first vane 131 is located at this circumferential center.Additionally, it is assumed that the angle increases in the rotationdirection M from this 0° angular position. In this case, while the firstvane 131 moves from the 0° angular position to the 240° angularposition, the fluid is drawn into the part chamber located on thetrailing side of the first vane 131.

In particular, since the front suction opening 141 a extends at leastfrom the leading edge of the second front flat surface 102 to the 120°angular position, the suction of the fluid continues until the firstvane 131 reaches the 240° angular position. This limits expansion of thefluid in this part chamber, thereby improving the efficiency.

While the second vane 131, which is on the trailing side of the firstvane 131, moves from the 120° angular position to the 360° angularposition, the fluid is compressed in the part chamber on the leadingside of the second vane 131.

The three front compression chambers A4 a to A4 c are at differentphases. That is, the space defined by the front rotating body surface71, the front fixed body surface 100, the tube outer circumferentialsurface 62, and the front cylinder inner circumferential surface 33 ispartitioned by the vanes 131 into three compression chambers atdifferent phases. In the present embodiment, while the rotating body 60rotates 480°, the suction and compression of fluid take place in each ofthe three front compression chambers and the three rear compressionchambers.

In the above description, the three front compression chambers A4 a toA4 c separated by the vanes 131 are defined in terms of the positionalrelationship with the front suction port 141 and the front dischargeports 151. However, the front compression chambers A4 a to A4 c may bedescribed from another viewpoint. For example, the following descriptionfocuses on one cycle in one compression chamber.

As the first vane 131 moves to the leading side of the second front flatsurface 102, a compression chamber continuous with the front suctionport 141 is provided on the trailing side of the first vane 131. Thiscompression chamber increases in volume as the vane 131 rotates, whilemaintained to be continuous with the front suction port 141. The fluidis thus drawn into this compression chamber.

Then, the second vane 131 moves to the leading side of the second frontflat surface 102, so that the compression chamber is defined by thefirst and second vanes 131. The fluid is drawn into this compressionchamber until the second vane 131 reaches the leading end of the frontsuction opening 141 a.

The second vane 131 continues to move beyond the leading end of thefront suction opening 141 a to the leading side, so that the compressionchamber is no longer continuous with the front suction port 141. As therotating body 60 rotates further, the compression chamber becomescontinuous with the front discharge ports 151. In this stage, the volumeof the compression chamber decreases as the rotating body 60 rotates,thereby compressing the fluid in the compression chamber. Then, when thesecond vane 131 reaches a position where it comes into contact with thesecond front flat surface 102, the volume of the compression chamberbecomes 0, and one cycle of suction and compression in the compressionchamber is completed.

The present embodiment has the following advantages.

(1-1) The compressor 10 includes the rotary shaft 12, the rotating body60, which rotates together with the rotary shaft 12, the fixed bodies 90and 110, which do not rotate together with the rotary shaft 12, and thevanes 131, which are inserted in the vane grooves 130 provided in therotating body 60 and rotate while moving in the axial direction Z as therotating body 60 rotates. The rotating body 60 has the rotating bodysurfaces 71 and 72 intersecting with the axial direction Z. The fixedbodies 90 and 110 have the fixed body surfaces 100 and 120, which facethe respective rotating body surfaces 71 and 72 in the axial directionZ. The compressor 10 includes the compression chambers A4 and A5 definedby the rotating body surfaces 71 and 72 and the fixed body surfaces 100and 120. The vanes 131 rotate while moving in the axial direction Z,causing the suction and compression of fluid in the compression chambersA4 and A5.

Each vane 131 includes the vane body 170, which is inserted in a vanegroove 130, and the tip seals (sealing members) 180 and 190, which areattached to the respective end faces 171, 172 of the vane body 170 inthe axial direction Z so as to be movable in the axial direction Zrelative to the vane body 170. The fluid (pressure) in each backpressure space 183, 193, which is provided between the vane body 170 andthe tip seal 180, 190, pushes the tip seal 180, 190 toward the fixedbody surface 100, 120 so that the tip seal 180, 190 is in contact withthe fixed body surface 100, 120.

The tip seal 180, 190, which is pressed by the fluid (pressure) in theback pressure space 183, 193 and thus in contact with the fixed bodysurface 100, 120, ensures the sealing between the vane 131 and the fixedbody surface 100, 120. A gap is therefore unlikely to be created betweenthe vane 131 and each fixed body surface 100, 120.

(1-2) The front compression chamber A4 includes the first part chamberAx and the second part chamber Ay located on the opposite sides of eachvane 131 in the circumferential direction. The first part chamber Ax islocated on the trailing side of the vane 131, and the second partchamber Ay is located on the leading side of the vane 131. Each end face171, 172 of the vane body 170 has the body attachment groove 173, 174,which is a body attachment section. Each tip seal 180, 190 includes theseal attachment protrusion 182, 192, which is attached to the bodyattachment groove 173, 174. The seal attachment protrusion 182, 192 andthe body attachment groove 173, 174 (specifically, the first body grooveside surface 173 b, 174 b) face each other in the circumferentialdirection of the rotary shaft 12.

In this configuration, when the vane 131 (specifically, the vane body170) rotates together with the rotating body 60, the seal attachmentprotrusion 182, 192 comes into contact with the body attachment groove173, 174 in the circumferential direction. This area of contact, whichis the side surface contact area Pb1, Pb2, ensures the sealing betweenthe vane body 170 and the tip seal 180, 190, thereby limiting movementof fluid between the two part chambers Ax and Ay through the backpressure space 183, 193.

(1-3) The present embodiment uses the body attachment grooves 173 and174, which are provided in the end faces 171 and 172 of the vane body170, as body attachment sections. Each body attachment groove 173, 174includes the first body groove side surface 173 b, 174 b, which is onthe trailing side, and the second body groove side surface 173 c, 174 c,which is on the leading side.

Each tip seal 180, 190 has the seal body 181, 191, which is in contactwith the fixed body surface 100, 120. The seal attachment protrusion182, 192 protrudes from the seal body 181, 191 toward the end face 171,172 of the vane body 170. The seal attachment protrusion 182, 192includes the first seal protrusion side surface 182 b, 192 b, which ison the trailing side, and the second seal protrusion side surface 182 c,192 c, which is on the leading side.

The tip seal 180, 190 is attached to the vane body 170 by inserting theseal attachment protrusion 182, 192 into the body attachment groove 173,174. The first seal protrusion side surface 182 b, 192 b and the firstbody groove side surface 173 b, 174 b face each other in thecircumferential direction.

In this configuration, the seal attachment protrusion 182, 192 isinserted in the body attachment groove 173, 174 so that the tip seal180, 190 is attached to the vane body 170. As such, the rotation of thevane 131 (specifically, the vane body 170) brings the first sealprotrusion side surface 182 b, 192 b into contact with the first bodygroove side surface 173 b, 174 b in the circumferential direction. Thisarea of contact, which is the side surface contact area Pb1, Pb2,ensures the sealing between the vane body 170 and the tip seal 180, 190.

In the present embodiment, each side surface contact area Pb1, Pb2extends in the axial direction Z. Thus, the contact between the firstseal protrusion side surface 182 b, 192 b and the first body groove sidesurface 173 b, 174 b is likely to be maintained even when the tip seal180, 190 moves toward the fixed body surface 100, 120. This limitsleakage of fluid through the back pressure spaces 183 and 193 andremoval of the tip seals 180 and 190.

(1-4) The contact between the first seal protrusion side surface 182 b,192 b and the first body groove side surface 173 b, 174 b increases thelikelihood that a clearance will separate the second seal protrusionside surface 182 c, 192 c from the second body groove side surface 173c, 174 c. This clearance facilitates the flow of fluid into the backpressure space 183, 193 from the second part chamber Ay. The fluid inthe second part chamber Ay tends to have a higher pressure than thefluid in the first part chamber Ax. For example, as for the vane 131separating the third front compression chamber A4 c from the secondfront compression chamber A4 b, the second front compression chamber A4b has a higher pressure. This increases the force of the fluid pushingthe tip seals 180 and 190 in the back pressure spaces 183 and 193. Thesealing between the vane 131 and the fixed body surfaces 100 and 120 isthus enhanced.

(1-5) Each tip seal 180, 190 includes the introduction grooves 184, 194for introducing the fluid into the back pressure space 183, 193 from thesecond part chamber Ay.

In this configuration, the introduction grooves 184 and 194 facilitatethe introduction of the fluid into the back pressure spaces 183 and 193from the second part chamber Ay. As such, the fluid in the second partchamber Ay, which tends to have a relatively high pressure, pushes eachtip seal 180, 190 toward the fixed body surface 100, 120. This furtherenhances the sealing between the vane 131 and the fixed body surfaces100 and 120.

(1-6) The introduction grooves 184, 194 are located closer to the secondpart chamber Ay than the side surface contact area Pb1, Pb2. The sidesurface contact area Pb1, Pb2 limits leakage of the fluid in the backpressure space 183, 193, which is introduced through the introductiongrooves 184, 194, into the first part chamber Ax. This helps to solvethe problem that the introduction grooves 184, 194 can cause leakage offluid from the second part chamber Ay into the first part chamber Ax.

(1-7) Each introduction groove 184, 194 extends along the second sealprotrusion side surface 182 c, 192 c and a section of the seal bodybottom surface 181 b, 191 b that is on the leading side of the sealattachment protrusion 182, 192.

In this configuration, even if the seal body bottom surface 181 b, 191 bis in contact with the end face 171, 172 of the vane body 170, the fluidin the second part chamber Ay can still flow into the back pressurespace 183, 193.

Second Embodiment

As shown in FIG. 16, in this embodiment, the first body groove sidesurfaces 212 and 215 and the second body groove side surfaces 213 and216 are tilted with respect to the axial direction Z such that the bodyattachment grooves 211 and 214 become gradually narrower as they deepen.In the present embodiment, each first body groove side surface 212, 215is displaced gradually toward the leading side in the rotation directionM as the body attachment groove 211, 214 deepens from the end face 171,172 of the vane body 170 (in other words, as it extends toward the bodygroove bottom surface 173 a, 174 a).

In accordance with the body attachment groove 211, 214 becominggradually narrower as it deepens, the seal attachment protrusion 221,224 becomes gradually narrower from the proximal end to the distal end.Specifically, in accordance with the inclination of the first bodygroove side surface 212, 215 and the second body groove side surface213, 216, the first seal protrusion side surface 222, 225 and the secondseal protrusion side surface 223, 226 are tilted with respect to theaxial direction Z. The first seal protrusion side surface 222, 225 isdisplaced gradually toward the leading side in the rotation direction Mfrom the proximal end to the distal end.

The first seal protrusion side surface 222, 225 and the first bodygroove side surface 212, 215 face each other in the circumferentialdirection. In this embodiment, these side surfaces are inclined at thesame angle. Likewise, the second seal protrusion side surface 223, 226and the second body groove side surface 213, 216 face each other in thecircumferential direction. In this embodiment, these side surfaces areinclined at the same angle.

In this configuration, when the vane 131 (specifically, the vane body170) rotates together with the rotating body 60, each first sealprotrusion side surface 222, 225 is brought into contact with the firstbody groove side surface 212, 215 in the circumferential direction.Accordingly, the side surface contact area Pb1, Pb2 is tilted withrespect to the axial direction Z.

In the same manner as the first embodiment, the back pressure space 183,193 is created between the tip seal 180, 190 and the vane body 170. Theback pressure space 183, 193 pushes the tip seal 180, 190 toward thefixed body surface 100, 120.

The present embodiment has the following advantages.

(2-1) Each first body groove side surface 212, 215 is tilted withrespect to the axial direction Z so as to be displaced gradually towardthe leading side in the rotation direction M as the body attachmentgroove 211, 214 deepens. The first seal protrusion side surface 222, 225is tilted with respect to the axial direction Z so as to be displacedgradually toward the leading side in the rotation direction M from theproximal end to the distal end. The first body groove side surface 212,215 and the first seal protrusion side surface 222, 225 face each otherin the circumferential direction.

In this configuration, when the vane body 170 rotates together with therotating body 60, the first seal protrusion side surface 222, 225 isbrought into contact with the first body groove side surface 212, 215,and the area of contact, which is the side surface contact area Pb1,Pb2, receives a pushing force F1, F2 acting in a direction orthogonal tothe side surface contact area Pb1, Pb2.

The side surface contact area Pb1, Pb2 is tilted with respect to theaxial direction Z so as to be displaced gradually toward the leadingside in the rotation direction M as it extends away from the fixed bodysurface 100, 120. As such, the pushing force F1, F2 includes a componentin the axial direction Z, specifically, a component in the directiontoward the fixed body surface 100, 120. This pushes the tip seal 180,190 toward the fixed body surface 100, 120, thereby enhancing thesealing at the distal end contact area Pa1, Pa2.

In the present embodiment, the second seal protrusion side surface 223,226 and the second body groove side surface 213, 216 are tilted withrespect to the axial direction Z, but these surfaces may be inclined inthe same direction and at the same angle as the first seal protrusionside surface 222, 225 and the first body groove side surface 212, 215.In this case, the width of the body attachment groove 211, 214 and thewidth of the seal attachment protrusion 221, 224 are uniform. The secondseal protrusion side surface 223, 226 and the second body groove sidesurface 213, 216 may be parallel to the axial direction Z. That is, thesecond seal protrusion side surface 223, 226 and the second body grooveside surface 213, 216 may have any configurations.

Third Embodiment

As shown in FIG. 17, in this embodiment, the seal attachment protrusions182 and 192 and the body attachment grooves 173 and 174 are closer tothe first part chamber Ax than to the second part chamber Ay.Specifically, the center line passing through the circumferential centerof the seal attachment protrusion 182, 192 and the body attachmentgroove 173, 174 is at a position displaced from the center line passingthrough the circumferential center of the tip seal 180, 190 toward thefirst part chamber Ax (in other words, at a position displaced towardthe trailing side). In the present embodiment, the side surface contactarea Pb1, Pb2 corresponds to the “area of contact between two attachmentsections.”

The operation of the present embodiment will now be described.

As shown in FIG. 17, each tip seal 180, 190 receives a first pushingforce Ff1, Fr1, which is applied by the fluid in the first part chamberAx, and a second pushing force Ff2, Fr2, which is applied by the fluidin the second part chamber Ay. The first pushing force Ff1, Fr1 acts ina direction orthogonal to the line connecting the distal end contactarea Pa1, Pa2 to the edge of the side surface contact area Pb1, Pb2 thatis closer to the seal body bottom surface 181 b, 191 b. The secondpushing force Ff2, Fr2 acts in a direction orthogonal to the lineconnecting the distal end contact area Pa1, Pa2 to the edge of the sidesurface contact area Pb1, Pb2 that is closer to the body groove bottomsurface 173 a, 174 a. The second pushing force Ff2, Fr2 is likely to belarger than the first pushing force Ff1, Fr1.

Since the second pushing force Ff2, Fr2 differs from the first pushingforce Ff1, Fr1 in magnitude and direction, there is an imbalance betweenthese forces. Each tip seal 180, 190 receives the resultant of the firstpushing force Ff1, Fr1 and the second pushing force Ff2, Fr2.

With this configuration, the inventors of the present application havefound that each tip seal 180, 190 receives a pushing force acting in adirection away from the fixed body surface 100, 120 when the distal endcontact area Pa1, Pa2, which is the area of contact between the sealsurface 181 a, 191 a and the fixed body surface 100, 120, is closer tothe first part chamber Ax than the side surface contact area Pb1, Pb2,in other words, when the distal end contact area Pa1, Pa2 is on thetrailing side of the side surface contact area Pb1, Pb2 in the rotationdirection M.

For example, as shown in the front part of FIG. 17, when the front tipseal 180 is in contact with the front curved surface 103 inclined upwardwith respect to the rotation direction M, the front distal end contactarea Pa1 is likely to be positioned on the leading side in the rotationdirection M of the front side surface contact area Pb1. Accordingly, theresultant of the front first pushing force Ff1 and the front secondpushing force Ff2 is likely to act in the direction toward the frontfixed body surface 100. This helps to push the front tip seal 180 towardthe front fixed body surface 100, enhancing the sealing at the frontdistal end contact area P1 a.

In contrast, at the rear side, the rear tip seal 190 is in contact withthe rear curved surface 123 inclined downward with respect to therotation direction M. Consequently, the rear distal end contact area Pa2is likely to be positioned on the trailing side of the center in thewidth direction of the rear seal surface 191 a. For this reason, therear distal end contact area Pa2 can be positioned on the trailing sideof the rear side surface contact area Pb2. In this case, the resultantof the first rear pushing force Fr1 and the second rear pushing forceFr2 is likely to act in a direction away from the rear fixed bodysurface 120.

In this respect, as shown in FIG. 17, the rear seal attachmentprotrusion 192 and the rear body attachment groove 174 of the presentembodiment are arranged to be closer to the first part chamber Ax, sothat the rear side surface contact area Pb2 is positioned near the firstpart chamber Ax. Accordingly, the rear distal end contact area Pa2 isless likely to be positioned on the trailing side of the rear sidesurface contact area Pb2, reducing the likelihood that the component inthe axial direction Z in the resultant of the first rear pushing forceFr1 and the second rear pushing force Fr2 will act in a direction awayfrom the rear fixed body surface 120. Further, even if the rear distalend contact area Pa2 is positioned on the trailing side of rear sidesurface contact area Pb2, the distance between these areas in thecircumferential direction and therefore the component of the forceacting in a direction away from the rear fixed body surface 120 would besmall. This limits separation of the rear tip seal 190 from the rearfixed body surface 120.

The present embodiment has the following advantages.

(3-1) Each fixed body surface 100, 120 is a ring-shaped surface andincludes the second flat surface 102, 122, which is a fixed body contactsurface in contact with the rotating body surface 71, 72, and the twocurved surfaces 103, 123 located on the opposite sides in thecircumferential direction of the second flat surface 102, 122. The twocurved surfaces 103, 123 are curved in the axial direction Z such thatthe distance to the rotating body surface 71, 72 gradually increases asthe curved surfaces 103, 123 extend away from the second flat surface102, 122 in the circumferential direction. The seal attachmentprotrusion 182, 192 and the body attachment groove 173, 174 are closerto the first part chamber Ax than to the second part chamber Ay. Inother words, the seal attachment protrusion 182, 192 and the bodyattachment groove 173, 174 are displaced from the circumferential centerof the tip seal 180, 190 toward the trailing side.

As such, the side surface contact area Pb1, Pb2 is displaced toward thetrailing side, reducing the likelihood that the distal end contact areaPa1, Pa2 will be located on the trailing side of the side surfacecontact area Pb1, Pb2. Further, even if the distal end contact area Pa1,Pa2 is positioned on the trailing side of the side surface contact areaPb1, Pb2, the distance between these contact areas would be small. Thisprevents or reduces the force acting on the tip seal 180, 190 in adirection away from the fixed body surface 100, 120. Accordingly, whenthe tip seal 180, 190 moves along the curved surface 103, 123 inclineddownward with respect to the rotation direction M, the sealing at thedistal end contact area Pa1, Pa2 is less likely to decrease.

Fourth Embodiment

The fourth embodiment will now be described. The fourth embodimentdiffers from the first embodiment in the attachment configurationbetween the vane body and the tip seal.

As shown in FIG. 18, in this embodiment, each seal body 181, 191 has aseal attachment groove 231, 234, which is recessed toward the fixed bodysurface 100, 120 from the seal body bottom surface 181 b, 191 b. Theseal attachment groove 231, 234, which serves as a seal attachmentsection, may have a width in the thickness direction of the vane 131 andextend in the radial direction R. Each seal attachment groove 231, 234has a first seal groove side surface 232, 235, which is on the trailingside in the rotation direction M, and a second seal groove side surface233, 236, which is on the leading side in the rotation direction M. Thesecond seal groove side surface 233, 236 is tilted with respect to theaxial direction Z so as to be displaced gradually toward the trailingside as the seal attachment groove 231, 234 deepens.

Each vane body 170 has body attachment protrusions 241 and 244protruding from the respective end faces 171 and 172 of the vane body170 toward the fixed body surfaces 100 and 120. Each body attachmentprotrusion 241, 244, which serves as a body attachment section, may be aridge that has a width in the thickness direction of the vane 131 andextends in the radial direction R. The body attachment protrusion 241,244 has a first body protrusion side surface 242, 245, which is on thetrailing side in the rotation direction M, and a second body protrusionside surface 243, 246, which is on the leading side in the rotationdirection M.

The second body protrusion side surface 243, 246 is tilted with respectto the axial direction Z so as to be displaced gradually toward thetrailing side from the proximal end to the distal end of the bodyattachment protrusion 241, 244.

The body attachment protrusion 241, 244 is a part of the vane body 170.The body attachment protrusion 241, 244 is made of a material harderthan the tip seal 180, 190, such as metal.

In this configuration, each body attachment protrusion 241, 244 isinserted in the seal attachment groove 231, 234 so that the tip seal180, 190 is attached to the vane body 170. The first seal groove sidesurface 232, 235 and the first body protrusion side surface 242, 245face each other in the circumferential direction, and the second sealgroove side surface 233, 236 and the second body protrusion side surface243, 246 face each other in the circumferential direction. Consequently,when the vane body 170 rotates together with the rotating body 60, thesecond body protrusion side surface 243, 246, which is the side surfaceon the leading side of the body attachment protrusion 241, 244, isbrought into contact with the second seal groove side surface 233, 236,which is the side surface on the leading side of the seal attachmentgroove 231, 234, in the circumferential direction. This area of contact(specifically, the side surface contact area Pb1, Pb2) provides sealingand blocks the fluid.

In the same manner as the first embodiment, the back pressure space 183,193 is created between each tip seal 180, 190 and the vane body 170. Theback pressure space 183, 193 pushes the tip seal 180, 190 to the fixedbody surface 100, 120.

The present embodiment has the following advantages.

(4-1) The tip seals 180 and 190 are made of a softer material than thevane body 170. Each tip seal 180, 190 has the seal body 181, 191, whichis in contact with the fixed body surface 100, 120. The seal body 181,191 has the seal body bottom surface 181 b, 191 b, which faces the endface 171, 172 of the vane body 170. Further, the tip seal 180, 190 hasthe seal attachment groove 231, 234, which is recessed from the sealbody bottom surface 181 b, 191 b. The vane body 170 has the bodyattachment protrusion 241, 244 protruding from each end face 171, 172 ofthe vane body 170. The body attachment protrusion 241, 244 is insertedin the seal attachment groove 231, 234 so that the tip seal 180, 190 isattached to the vane body 170.

In this configuration, the body attachment protrusion 241, 244 isinserted in the seal attachment groove 231, 234 so that the tip seal180, 190 is attached to the vane body 170. This configuration reducesremoval of the tip seals 180 and 190, as compared to the firstembodiment in which the seal attachment protrusions 182 and 192 areinserted in the respective body attachment grooves 173 and 174.

Specifically, in a configuration in which each seal attachmentprotrusion 182, 192 is inserted in the body attachment groove 173, 174as in the first embodiment, the seal attachment protrusion 182, 192 mayfail to have a high rigidity and thus deform, resulting in removal ofthe tip seal 180, 190 from the vane body 170.

The tip seal 180, 190, which serves as a sealing member, is made of asoft material that easily deforms to increase the sealing performance.For this reason, the tip seal 180, 190 is likely to have a low rigidity,which may result in the removal.

In contrast, the present embodiment inserts each body attachmentprotrusion 241, 244 of the vane body 170 into the seal attachment groove231, 234. The body attachment protrusion 241, 244 is a part of the vanebody 170, which is harder than the tip seals 180 and 190, and thusresists deformation as compared to the tip seals 180 and 190 (the sealattachment protrusions 182 and 192). Further, as compared to theconfiguration including the seal attachment protrusions 182 and 192, theconfiguration including the seal attachment grooves 231 and 234 allowsthe tip seals 180 and 190 to have a higher rigidity. This reduces theproblem that the tip seals 180 and 190 are deformed and removed from thevane body 170.

(4-2) Each seal attachment groove 231, 234 has the first seal grooveside surface 232, 235 on the trailing side and the second seal grooveside surface 233, 236 on the leading side. Each body attachmentprotrusion 241, 244 has the first body protrusion side surface 242, 245on the trailing side and the second body protrusion side surface 243,246 on the leading side. The second body protrusion side surface 243,246 and the second seal groove side surface 233, 236 face each other inthe circumferential direction.

The second seal groove side surface 233, 236 is tilted with respect tothe axial direction Z so as to be displaced gradually toward thetrailing side as the seal attachment groove 231, 234 deepens. The secondbody protrusion side surface 243, 246 is tilted with respect to theaxial direction Z so as to be displaced gradually toward the trailingside from the proximal end to the distal end of the body attachmentprotrusion 241, 244.

In this configuration, when the vane body 170 rotates together with therotating body 60, each second body protrusion side surface 243, 246 isbrought into contact with the second seal groove side surface 233, 236.Through this area of contact, which is the side surface contact area PM,Pb2, the tip seal 180, 190 receives the pushing force F1, F2 including acomponent acting in the direction toward the fixed body surface 100,120. The pushing force F1, F2 pushes the tip seal 180, 190 against thefixed body surface 100, 120, thereby enhancing the sealing at the distalend contact area Pa1, Pa2.

The embodiments described above may be modified as follows. Theembodiments and the following modifications may be combined to theextent that does not cause technical contradiction.

As shown in FIG. 19, in the configuration in which each body attachmentgroove 173, 174 is provided at the circumferential center (the center inthe width direction) of the vane body 170, the width D1, D2 of the bodyattachment groove 173, 174 may be greater than half the vane width D0,which is the width of the vane 131. In this case, the width of the sealattachment protrusion 182, 192 may be increased according to the bodyattachment groove 173, 174.

In this configuration, the increased width D1, D2 of the body attachmentgroove 173, 174 allows the side surface contact area Pb1, Pb2 to becloser to the first part chamber Ax accordingly. This configuration thushas Advantage (3-1) described above.

The introduction grooves 184 and 194 may be provided in the vane body170 instead of the tip seals 180 and 190, or may be provided in both ofthe tip seals 180 and 190 and the vane body 170. That is, anyconfiguration may be used as long as an introduction groove 184, 194 isprovided in at least one of the tip seal 180, 190 and the vane body 170.

The introduction grooves 184 and 194 may be omitted.

The shape and the position of the tip seals 180 and 190 may be changedfreely as long as they are attached to the vane body 170 so as to bemovable in the axial direction Z.

One of the tip seals 180 and 190 may be omitted. That is, the tip sealmay be provided only on one of the front side and the rear side. In thiscase, the end of the vane body 170 that does not include a tip sealpreferably has a seal surface that is in contact with a fixed bodysurface. That is, the vane 131 may be composed of two parts of a vanebody and one tip seal.

As long as the seal attachment protrusion 182, 192 and the bodyattachment groove 173, 174 face each other, they may be in contact witheach other in the circumferential direction or spaced apart from eachother when the rotating body 60 is not rotating. The same applies to thebody attachment protrusions 241 and 244 and the seal attachment grooves231 and 234.

The rotating body surfaces 71 and 72 may be tilted with respect to theaxial direction Z. In this case, the front flat surfaces 101 and 102 andthe rear flat surfaces 121 and 122 may be orthogonal to the axialdirection Z, or inclined at the same angle as the rotating body surfaces71 and 72 so as to be in planar contact with the rotating body surfaces71 and 72.

The rotating body tube 61 may include a cutout section or a protrusion.In the embodiments described above, the rotating body tube 61 iscylindrical, that is, has a circular cross-section, but may have anon-circular cross section. As long as each fixed body insertion hole91, 111 is shaped corresponding to the shape of the rotating body tube61 so as to reduce a gap between the inner wall surface defining thefixed body insertion hole 91, 111 and the rotating body tube 61, thefixed body insertion hole 91, 111 does not have to be circular. Inaddition, when the rotating body tube 61 has a cutout section, anadditional member may be fitted into the cutout section.

The rotating body may be a circular plate that does not have anyprojection extending from the rotating body surfaces 71 and 72 in theaxial direction Z. The rotating body does not have to be supported bythe two fixed bodies 90 and 110. In this case, the front compressionchamber A4 may be defined by the outer circumferential surface of therotary shaft 12. That is, the front compression chamber A4 does not haveto be defined by the tube outer circumferential surface 62 and may haveany configuration as long as it is defined by the front rotating bodysurface 71 and the front fixed body surface 100. The same applies to therear compression chamber A5.

The number of the shaft bearings 51 and 53 is not limited to two and maybe one. For example, the rear shaft bearing 53 may be omitted. Three ormore shaft bearings may be provided.

In the present embodiment, the front cylinder 30 and the rear plate 40define the accommodation chamber A3. However, the accommodation chamberA3 may be defined in any manner.

For example, the compressor 10 may include a front plate instead of thefront cylinder 30. Further, instead of the rear plate 40, the compressor10 may include a rear cylinder having a circumferential wall and an endwall. In this case, the rear cylinder is butted against the front plateto define the accommodation chamber A3.

Alternatively, the compressor 10 may include two cylinders that definethe accommodation chamber A3. Further, the rear plate 40 may be omitted,and the accommodation chamber A3 may be defined by the front cylinder 30and the rear housing end wall 23.

As long as each compression chamber A4, A5 is defined by the rotatingbody surface 71, 72 and the fixed body surface 100, 120, the othersurfaces defining the compression chamber A4, A5 may be changed. Forexample, in a configuration in which the front cylinder 30 is omittedand the rear housing member 22 (or the housing 11) accommodates therotating body 60 and the fixed bodies 90 and 110, the compressionchambers A4 and A5 may be defined by the inner circumference surface ofthe rear housing member 22, instead of the front cylinder innercircumferential surface 33. In this case, the rear housing member 22 orthe housing 11 may be considered as the cylinder portion accommodatingthe rotating body and the fixed bodies, and the inner circumferencesurface of the rear housing member 22 may be considered as the cylinderinner surface defining the compression chambers together with therotating body surfaces and the fixed body surfaces. Further, thecompression chambers A4 and A5 may be defined by the outercircumferential surface of the rotary shaft 12 instead of the tube outercircumferential surface 62.

The front fixed body 90 and the front cylinder 30 may be formedintegrally, and the rear fixed body 110 and the rear plate 40 may beformed integrally.

The configuration for introducing the fluid into the compressionchambers A4 and A5 and the configuration for discharging the fluidcompressed in the compression chambers A4 and A5 are not limited to theconfigurations described in the first embodiment. For example, at leastone of the suction port and the discharge port may be provided in thefixed bodies 90 and 110.

The two fixed bodies 90 and 110 have the same shape. However, thepresent disclosure is not limited to this. For example, the front fixedbody 90 may have a larger diameter than the rear fixed body 110, or viceversa. In this case, the front cylinder inner circumferential surface 33may have steps corresponding to the shapes of the fixed bodies 90 and110, or a front cylinder accommodating the front fixed body 90 may beprovided separately from a rear cylinder accommodating the rear fixedbody 110. That is, the volumes of the two compression chambers A4 and A5may be the same or different.

The compressor 10 of the embodiments has the two compression chambers A4and A5, but the present disclosure is not limited to this.

For example, as shown in FIG. 20, the rear fixed body 110, the rearcompression chamber A5, the rear suction port 142, and the reardischarge ports 161 may be omitted. In this case, the front fixed bodysurface 100 does not have to include the first front flat surface 101.In FIG. 20, each vane 131 has the rear tip seal 190, but the rear tipseal 190 may be omitted.

In this case, an urging portion 300 may be provided that urges the vane131 toward the front fixed body 90. The urging portion 300 may besupported by an urging support section 301 provided in the rotating bodytube 61 so as to be rotatable together with the rotating body 60. Theurging support section 301 may be plate-shaped and protrude radiallyoutward from the rear rotating body end 61 b of the rotating body tube61. As such, the vane 131 remains in contact with the front fixed bodysurface 100 while rotating and moving in the axial direction Z alongwith the rotation of the rotating body 60. Instead of omitting the rearside configuration, the front side configuration may be omitted. Inother words, the compressor 10 may include only one fixed body.

The fixed body insertion holes 91 and 111 do not have to be throughholes and may have closed ends, as long as they receive the rotary shaft12.

At least one of the thrust bearings 81 and 82 may be omitted. That is,the compressor 10 does not have to include the thrust bearings 81 and82.

At least one of the two rotating body bearings 94 and 114 may beomitted.

The discharge chamber A1 is not required to have the shape of a cylinderwith the axis extending in the axial direction Z. For example, thedischarge chamber A1 may be C-shaped as viewed in the axial direction Z,or two discharge chambers A1 may be arranged to face each other. Inother words, the discharge chamber A1 may be configured to extend atleast partially in the circumferential direction.

The number of the vanes 131 is arbitrary, and may be one, two, or fouror more. When only one vane 131 is provided, the front compressionchamber A4 is partitioned into a chamber for suction and a chamber forcompression by the vane 131 and the area of contact between the secondfront flat surface 102 and the front rotating body surface 71.

The area of the front fixed body surface 100 that is in contact with thefront rotating body surface 71 (the fixed body contact surface) does nothave to be a flat surface like the second front flat surface 102. Thesame applies to the rear fixed body surface 120. Nevertheless, a flatsurface is desirable in view of the sealing performance.

The fixed body contact surface may be omitted. For example, a small gapmay separate the second front flat surface 102 from the front rotatingbody surface 71.

The housing 11 may have an arbitrary shape.

The rotary shaft 12 may have an arbitrary shape. For example, at least apart of the rotary shaft 12 may be hollow or has the shape of a prism.

The electric motor 13 and the inverter 14 may be omitted. That is, thecompressor 10 does not have to include the electric motor 13 or theinverter 14. In this case, the rotary shaft 12 may be driven and rotatedby a belt, for example.

The compressor 10 may be used for other than an air conditioner. Forexample, the compressor 10 may be used to supply compressed air to afuel cell mounted on a fuel cell vehicle. That is, the fluid compressedby the compressor 10 is not limited to a refrigerant containing oil.

The compressor 10 may be mounted on an object other than a vehicle.

Various changes in form and details may be made to the examples abovewithout departing from the spirit and scope of the claims and theirequivalents. The examples are for the sake of description only, and notfor purposes of limitation. Descriptions of features in each example areto be considered as being applicable to similar features or aspects inother examples. Suitable results may be achieved if sequences areperformed in a different order, and/or if components in a describedsystem, architecture, device, or circuit are combined differently,and/or replaced or supplemented by other components or theirequivalents. The scope of the disclosure is not defined by the detaileddescription, but by the claims and their equivalents. All variationswithin the scope of the claims and their equivalents are included in thedisclosure.

What is claimed is:
 1. A compressor comprising: a rotary shaft; arotating body that is configured to rotate together with the rotaryshaft and includes a rotating body surface, which intersects with anaxial direction of the rotary shaft, and a vane groove and; a fixed bodythat is configured not to rotate together with the rotary shaft andincludes a fixed body surface, which faces the rotating body surface inthe axial direction; a vane that is inserted in the vane groove andconfigured to rotate together with the rotating body while moving in theaxial direction; and a compression chamber that is defined by therotating body surface and the fixed body surface and in which suctionand compression of fluid is performed when the vane rotates while movingin the axial direction, wherein the vane includes a vane body insertedin the vane groove, and a sealing member attached to an end face in theaxial direction of the vane body so as to be movable in the axialdirection relative to the vane body, a back pressure space is locatedbetween the sealing member and the vane body, and the sealing member isconfigured to be pressed by the back pressure space toward the fixedbody surface so as to be in contact with the fixed body surface.
 2. Thecompressor according to claim 1, wherein the compression chamberincludes a first part chamber located on a trailing side of the vane ina rotation direction of the rotating body, and a second part chamberlocated on a leading side of the vane in the rotation direction, thesealing member includes a seal attachment section attached to a bodyattachment section located in the end face of the vane body, and thebody attachment section and the seal attachment section face each otherin a circumferential direction of the rotary shaft.
 3. The compressoraccording to claim 2, wherein the body attachment section is a bodyattachment groove that is located in the end face of the vane body, hasa width in a thickness direction of the vane, and extends in a radialdirection of the rotary shaft, the body attachment groove includes afirst body groove side surface and a second body groove side surface,which is on the leading side of the first body groove side surface inthe rotation direction, the sealing member includes a seal body that isin contact with the fixed body surface, the seal attachment section is aseal attachment protrusion that protrudes from the seal body toward theend face of the vane body, the seal attachment protrusion includes afirst seal protrusion side surface and a second seal protrusion sidesurface, which is on the leading side of the first seal protrusion sidesurface in the rotation direction, the seal attachment protrusion isinserted in the body attachment groove so that the sealing member isattached to the vane body, and the first seal protrusion side surfaceand the first body groove side surface face each other in thecircumferential direction.
 4. The compressor according to claim 3,wherein at least one of the vane body and the sealing member has anintroduction groove configured to introduce fluid into the back pressurespace from the second part chamber.
 5. The compressor according to claim3, wherein the first body groove side surface is tilted with respect tothe axial direction so as to be displaced gradually toward the leadingside in the rotation direction as the body attachment groove deepens,and the first seal protrusion side surface is tilted with respect to theaxial direction so as to be displaced gradually toward the leading sidein the rotation direction from a proximal end to a distal end of theseal attachment protrusion.
 6. The compressor according to claim 3,wherein the fixed body surface includes a fixed body contact surfacethat is in contact with the rotating body surface; and two curvedsurfaces that are located on opposite sides of the fixed body contactsurface in the circumferential direction and curved in the axialdirection such that a distance to the rotating body surface graduallyincreases as the curved surfaces extend away from the fixed body contactsurface in the circumferential direction, and the body attachment grooveand the seal attachment protrusion are closer to the first part chamberthan to the second part chamber so that a side surface contact area,which is an area of contact between the first seal protrusion sidesurface and the first body groove side surface, is closer to the firstpart chamber than to the second part chamber.
 7. The compressoraccording to claim 2, wherein the sealing member is made of a materialsofter than the vane body, the sealing member has a seal body that is incontact with the fixed body surface, the seal body has a seal bodybottom surface that faces the end face of the vane body, the sealattachment section is a seal attachment groove recessed from the sealbody bottom surface, the body attachment section is a body attachmentprotrusion protruding from the end face of the vane body, and the bodyattachment protrusion is inserted in the seal attachment groove so thatthe sealing member is attached to the vane body.
 8. The compressoraccording to claim 7, wherein the seal attachment groove includes afirst seal groove side surface and a second seal groove side surface,which is located on the leading side of the first seal groove sidesurface in the rotation direction, the body attachment protrusionincludes a first body protrusion side surface and a second bodyprotrusion side surface, which is located on the leading side of thefirst body protrusion side surface in the rotation direction, the secondseal groove side surface is tilted with respect to the axial directionso as to be displaced gradually toward the trailing side in the rotationdirection as the seal attachment groove deepens, the second bodyprotrusion side surface is tilted with respect to the axial direction soas to be displaced gradually toward the trailing side from a proximalend to a distal end of the body attachment protrusion, and the secondbody protrusion side surface and the second seal groove side surfaceface each other in the circumferential direction.